He warns that any new controls on imports and exports of food would increase costs and transport times, making it harder to get fresh items to customers.

"If you take our fresh produce supply chains, for example, we put things on a lorry in Spain and it will arrive in a distribution centre somewhere in England, and it won't have gone through any border checks," he said.

"Anything that encumbers that has two effects: it adds cost, and it also has a detrimental effect on freshness - if you're shipping fresh produce from a long distance, even a few hours of delay can make a material impact."

This will also affect British fresh food producers supplying stores in the Republic of Ireland where many British retailers have a large presence.

Industry body the British Retail Consortium warned last week that British shoppers could face higher prices and less choice unless Britain and the EU can agree how to handle issues such as border checks, haulage and food safety after Brexit.

1. Price-per-unit is king.

The entire goal of a bulk buy is to make sure that the cost per unit is as low as you can possibly get it, then buying a ton when that cost per unit is low. Thus, to really maximize a bulk buy, you need to know how to calculate cost per unit quickly and efficiently.

Cost per unit, in concept, is really easy to calculate. A “unit” is the actual amount of something you’re getting. A roll of toilet paper is not a unit. However, a square foot of toilet paper is a unit. A bottle of ketchup is not a unit. However, a fluid ounce of ketchup is a unit. An actual unit will always directly relate to how much you use, so a bottle of ketchup might be used a varying amount depending on the size of the bottle, but you’ll usually use an ounce of ketchup the same way regardless of the bottle it’s in.

Cost per unit requires you to figure out how many units you would actually be buying (usually multiplication). Then, you take the total cost of your purchase and divide that by the number of units.

What you are always looking for are situations where you can push the cost per unit at least 50% below what you would normally pay. Usually, the large versions of the items have a lower cost per unit, but it’s worth calculating it in each case.

2. Never bulk buy an item you haven’t tried before.

You may find that the product doesn’t meet your needs, even if you expect that it will.

For example, I bulk bought a particular type of men’s body wash a while back, only to find out that it dried out my skin something fierce. It gave my skin a feel that could be described as crunchy or crispy. That’s not something you want in a soap that you’re going to use daily for the next several months.

I’ve bought trash bags where the bottom has ripped out of nearly every other bag. I’ve bought hand soap that didn’t lather. I can go on and on with examples of products that seem like they would work but simply do not.

Don’t waste your time bulk buying an item unless you’ve personally used it and you know that it works for your needs.

3. Never bulk buy perishable goods unless you’re going to go home and process all of it immediately.

We rarely buy anything perishable in bulk. On the rare occasions when we have done so, we’ve gone home and used all of it within a day or two, either directly in meals or by canning or freezing it.

Sometimes, you will find stupendous deals on fresh items if you buy a lot of them. For example, I once bought about fifty pounds of tomatoes for the price of about five.

The problem is that even if you save 50% or 75% off of the item, if you don’t use a significant portion of that item, you’re not saving money. Even then, you still have to deal with getting rid of the excess. With perishables, your window of opportunity to use the item is limited and the cleanup of the excess can be messy.

If you have a plan for all of it – say, going home and making four fresh lasagnas and freezing the rest of the tomatoes you just bought – then it can still be a good buy. Without a plan, though, a bulk buy of a perishable item is more trouble than it’s worth.

4. Stack coupons and sales when bulk buying.

The best time to bulk buy is when you can stack coupons on top of bulk purchases. With a bit of planning, you can do this really well, especially if there are no limits.

When I browse through coupons, if I happen to notice a particularly good one, I’ll print off several copies of that coupon. Then, I’ll hold onto them and wait until there’s a sale – and, surprisingly often, the local stores will have a sale on that item well before the coupons expire. At that point, I’ll go in there and drop all of the coupons at once on top of that sale.

Most stores will work with you on this, particularly if the sale doesn’t have a limit. Explain that you want to use these coupons before you go through and they’ll make it work for you.

Remember, the goal is to minimize the cost per unit, and using a coupon on top of a sale achieves that quite effectively.

5. Ensure you have adequate storage space before you buy.

If you don’t have a place to put the stuff, you’re going to find yourself in a pretty serious pickle when you get home. If you’re thinking of buying something in bulk, make sure you have storage space before you make that purchase.

Also, it’s worth noting that you should never, ever consider increasing your living space just so you can swing more bulk buys. If you’re looking at a home and are leaning toward a more expensive one because of a roomier basement for your bulk purchases, then you need to re-think things. Getting a bigger mortgage, paying more property taxes, and having higher utility costs so you can store some extra bulk items is not a wise financial decision.

Many families in our area have a storage room in the basement that also doubles as a tornado or storm shelter (we have one, but it functions as a laundry room for us). This is a great spot for stowing away bulk purchases so that they don’t take up kitchen space.

6. Don’t pin yourself against the wall by running out of non-perishables.

If you get into a routine of buying in bulk, you’ll start to get used to just heading to the place where you keep those purchases and refilling whenever you need something. Of course, even with bulk purchases, you’ll run out eventually – and then, if you need something, you’re up against the wall.

A good routine to establish is whenever you see that you only have one or two items left out of your bulk stash of a particular item, start actively looking for a bargain on that item. Some items go faster than others, so keep that in mind. I like to make sure I’m good for at least one full month with most non-perishables.

Generally, if I know I have enough of an item already, I don’t even look at sales on that item, but sometimes something absurd jumps on you. I recently purchased a ton of men’s body wash for roughly a quarter a bottle. I’m now sitting on quite a few bottles, but I’m probably going to donate some to the local food pantry.

7. Don’t bulk buy everything at once unless you have an enormous bankroll.

When people first start getting into bulk buying, they often go crazy and buy everything in bulk, spending themselves into debt. You do not want to start off by heading to the store and dropping several hundred dollars if you don’t have it in hand.

A much better approach is to simply raise your household supply budget by about 25% for several months. Use that extra 25% to engage in some bulk buying, taking advantage of big sales when you see them.

Eventually, you won’t need that extra 25%. In fact, your household budget will now be significantly lower than it was before because most of your household purchases are simply irregular refills of things you already bought in bulk, plus you now can sit and wait for the truly good discounts.

Don’t do it all at once unless you have that cash easily available or you undo the financial advantages of bulk buying.

8. Split up bulk buys with friends and family.

A final tip: if you see a really big bulk purchase that could save you a lot of money – like a 50 pound bag of rice or something like that – but you just can’t deal with the amount you’d be buying, talk to some friends. If you can get three friends to split that huge bag of rice with you, you’ll each wind up with 12.5 pounds of rice, which is much more tolerable, plus three of your friends got the same discount.

I’ll often check with people in my area on social media for these kinds of bulk purchases. If you can find a few people who want to jump on board, just go ahead and buy it, then split it up into equal amounts and figure out what everyone owes you.

Sure, you might end up getting stuck with a double portion of a bulk buy, but you can always turn to your friends to get rid of that via someone else.

Bulk buying really can save you a lot of money, but you can’t just charge in. Plan things in advance a little bit and you’ll be very glad you did.

If you live in shared accommodation, think about having an arrangement with your flatmates so you can all save a bit of money when it comes to shopping for the flat.

Buying in bulk is often cheaper, so if you pool your cash for certain items, it could knock a big chunk off your weekly bill.

For example, buying toilet paper in bulk and splitting the cost between a number of people is way more effective than if you all individually buy a two roll pack every other day (what even is the point in two-roll packs?).

Make sure you always do the math before buying in bulk though, as sometimes you’ll find that you’re not actually getting a better deal – despite what the supermarket would like you to think. Sometimes a deal is not a deal...

Most of us don’t really think about the time of day that we choose to do our food shopping. When you have lectures, seminars and a busy social life to work around, we tend to just squeeze it in wherever we can.

However, for the best bargains, you should try to shopping later in the day, ideally an hour or so before closing time or in 24 hour stores about 7pm. Stores often have offers on perishable items which are near their expiry date. Many of these items can still be used or frozen to use at a later date. The problem for the supermarket is that nobody will buy them if the date is passed so they are just thrown away – just keep your eye peeled for the yellow "reduced" stickers.

Remember too that best before end dates aren’t set in stone.

The latest survey from Kantor Worldpanel show that Dunnes Stores has increased its grocery market share from 22.9% in the 12 weeks up to February 26 2017. The same time last year the market share was 22.5%.

Sales in Dunnes increased by 4.6% over the period helped by consumers spending an extra €3 per shopping trip.

Supervalu are right behind with a 22.6% market share. They managed to increase sales by 0.5% or an extra €1 per trip.

Lidl and Aldi have also continued to increased their share up to 10.6% and 10.8% respectively.

Most of these gains have been at the expense of Tesco which has suffered a drop in sales of 1%, mostly due to 11 strike days during the period. Tesco's market share has fallen from 22.6% to 21.7%.

When it comes to food shopping, we tend to be creatures of habit. We normally opt for the same stores to buy our groceries, as this is what we’re used to.

Or, quite reasonably, we’ll go to the supermarket round the corner from where we live, because it’s easy to get to (even if it’s a convenience store with crazy mark-ups).

But, to get the best savings possible, we should leave our comfort zone and try budget chains like Lidl and Aldi. They offer some brilliant deals for those who are willing to try something different. The product quality is excellent and the prices are great! The only problem is you are likely to go looking for cornflakes and come back with a chainsaw :-).

Same goes for shopping at local markets when they’re on as well as smaller, independent stores. If we shop around and we can get some serious savings!

Since these products have a high turnover and in particular with dairy products, it is easier to deliver to the rear of the store where goods can be stored in large refrigerated storage areas before they are put on the shop floor.

So, next time you are trekking across the store to get your essential, just remember they may be trying to get you to spend more but also make it easier to manage their deliveries.

Locals complain that it stops people from moving freely from Dunnes to the centre of the town. In reality, the reason is more commercial. Dunnes recently took the top spot in the Irish grocery market with a 22.7% market share followed closely by SuperValu at 22.5%.

Retailers rely on what is called the Geography of Avoidance. What this really means is that they physically make it difficult for people to shop around. In this case, for a shopper to compare prices they will have to have to spend ten minutes to go right around to the SuperValu store, where as before they could more between the locations in in few minutes. This makes shoppers likely to do all the shopping in one location as the savings would have to be worth more than the effort.

Another example of this is the trend towards bigger and bigger stores in recent years. The bigger the store, the more effort it is to leave the store, cross the vast car park to go to another store to check the prices.

That is one of the reasons why the ShoppingBud app exists, you can compare the prices no matter where you are, regardless of walls.

Products like washing powder and potato waffles can be up to 30% cheaper in the UK compared to the ROI even from the same retailer (ie Tesco).

Pricing Differences

It is easiest to spot the difference when comparing Branded products.

Product		IRL		UK
		Tesco	SuperValu	Tesco	Sainsbury's	ASDA
	Birds Eye 18 Potato Waffles 1.02Kg	€3.39	€3.00	€2.35 (£2.00)	n/a	n/a
	Heinz Baked Beans 415G	€1.04	€1.05	€0.88 (£0.75)	€0.88 (£0.75)	€0.88 (£0.75)
	Kelloggs Corn Flakes 1KG	€3.99	€3.50	n/a	€3.53 (£3.00)	n/a
	Persil Non-Bio. Washing Powder 23 Wash 1.61Kg	€10.10	€9.44	€7.07 (£6.00)	€7.07 (£6.00)	€4.71 (£4.00)

Some products are not available (n/a) in the same size at certain stores.

*Prices and exchange rates as of 20/02/2017

Why is the price in Ireland so out of kilter with the price in the UK? Most of these products are sourced from the same supply chain. Look like someone is making a great margin on products in Ireland.

It is likely that the Brexit process over the next couple of years will significantly affect prices in the UK and if Retailers insist in trying to maintain high margins then there is a good likelihood that future consumers will be more inclined to look at comparable products which reflect better value.

Paddy might be relaxed but they are not stupid!!

Supermarkets train customers to recognise discounts and special offers. In this case customers are trained to expect that yellow labels indicate an offer which represents good value. However this can just serve to draw your attention from better value options.

It really pays to stay on your toes and do the maths on so-called “special offers”. Don’t just trust the brightly coloured discount signs that are designed to make you think you’ve found a bargain.