Is it a friend or someone you know professionally? If it is a friend/family then maybe you could try to convince them to let you have it for free for a bit (as they aren't using it anyway), after all, what costs is it going to incur for them if you pay for any maintenance it needs?
If it someone professional, it is obviously completely different. I don't know the going rates but I would assume something like $50 P/W would be appropriate? If you are clever with your locations, you should make that in one day, and therefore are into profits for the next 6 days of the week (depending on when and how long you plan to work for)
They are just predictions, but hopefully they can help.
Luke
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