worth a mention, if it is in B&Q then compare with screwfix before you buy if possible
same owner company and sometimes the screwfix price is a LOT less than B&Q, and they are usually spread out as well.
Obviously not for wood but for screws and suchlike, hardware and that sort of item.
I needed a lot of ground cover weed matting as doing a lot of patio work in the back garden (1 smallish shed base, 1 large shed base and a small base for a chicken coop) and had 100 meters for £30, B&Q had 30 meters for £31, so pretty much 1/3rd of the price per meter. I still have loads left, but previously we spent £90 on 3 rolls and a few months later checked screwfix and found the price difference...
Also for tradepoint you need to prove you are a trader, however they don't ask for a VAT number and dont seem to check too deeply. I still have the card and doing the kitchen and other work in the garden have saved substantial amounts of cash, discount varies on the items but doing 3 raised beds with 2 rows of flags we saw around a 20-25% discount, and noticed that when there are multi-pack offers (ie 5 planks for £25 or £7 each) you get the single items at the rate of the multipack.
so if you use them a lot it is worth asking about tradepoint.....