what would you advise folk not to buy !!!!!!!

[Timelord]

Don't buy crap from China! (That's most stuff they export).
Don't buy heavy lardy kit if you intend to carry it in your bug out gear.
Don't buy lots of cheap stuff if you intend to bug out. Buy quality instead and watch the bulk & weight.
Don't buy gold if you intend to bug out on foot with it. In that scenario it will be a liability & worthless. Silver possibly the same. You could always bury it for the archaeologists of the future to dig up.
We live in a materialistic society of excess. Why would you need precious metals to barter with PSHTF, when there is material excess everywhere around us. Some of this will be far more valuable than precious metals if it is a bad PSHTF scenario.

Don't put your confidence in buying a big 4x4 vehicle or any vehicle for that matter for a bug out scenario in the UK, especially for PSHTF. It would be handy to have and could be a useful tool, but be aware the myriad of possible SHTF scenarios may rule out travel by vehicle. Have alternative plans.
Don't buy cheap xbows etc, as they are no better than a toy and the build quality is crap - ref first sentence. Bits can break off easily due to flimsy construction. Don't buy plastic bolts other than for training - then again why shoot something different for training than you would for the real thing. Alloy bolts are not that much better anyway.

Don't buy cheap batteries or any of the 98% of ebay listed ones, as they are mostly Chinese fakes - ref first sentence.

Don't buy cheap nylon tents. Check the Hydrostatic head first and the seam construction. Too many cheap tent - you buy mister - tent luv u long time.. no..

Don't buy a backup GPS system for PSHTF. Oh how I laugh!! and it goes on ....