Tricky tricky tricky. There has to be trust, and something drawn out that says he has this responsibility, and you have this responsibility. However before you get into all that, each one of those ideas yall have talked about, you need to sit down and come up with the pros and cons to each. The one that has the most pros is the one I would go with. It seems to me that for the most part, all of these are a different job function.
However I will give this extra advice on the last one. Were you will be going to auctions and making bids, and he wants you to do that for him too. I would scratch that out. Remember there are ways to offset the odds with this industry. But still can be a gamble. Say you bid on a locker that to you can make $800. So you bid it up to $450 and get it. His $450 mind you. And after all said and done, everything is sorted, and you only manage to make $175 on it all. Now you got to explain to him where the other $275 is at. Well it jsut was not there, you made a wrong calculation, you read the locker wrong, what you thought you saw was in no shape to make you the money you thought you could make. Then what?
I say this cause my brother in law approached me with the same deal. And after weighing all this out, and told him sorry I cant do it. Just what if I use your money to get a locker and its a bust, then im lost out and so are you. Just not worth it.