I have to point something out. We live in the 4 Corners area, and there are a TON of Brits who come & vacation here. We see them at the Wal-Mart every weekend when we do our shopping, and they are invariably flashing serious cash around. I'm talking wads of $100 bills, and they're just standing at the cash register, pulling them out of their wallets, waving them around, walking around the store counting their money, etc.
I can only assume that Britain is a far safer place than the US, but here, you are just waving a red flag of "Victim!" in front of potential criminals' faces if you wave wads of cash through the air and act careless with it. I just wanted to point out, for tourists from other countries, the best thing to do is to, rather than getting out several thousands of US dollars, use a credit card. And, if for whatever reason, you have to have several thousand dollars, I would probably leave it locked in the hotel safe, or hide it somewhere in the rental house, rather than carrying it about on my person.
When you do go to a store, don't take out more than the money you need. Leave the rest concealed in your wallet. There is no need to show thieves that you're toting serious cash around. When you get change back, just put it straight into your wallet, discreetly, before you leave the register. Walking away from the register with money in your hand and your wallet open is not a good idea, because someone could just yoink! it away from you.
Just wanted to point this out, as we see this happening several times, every single time we go shopping, and it is always British tourists who seem to be waving the major cash around. Wal-Mart parking lots are never the safest places to be, particularly if you're walking around with an open wallet, showing everyone a stack of $100's nestled inside!
Cheers!
Heather W