Honestly, an American-based independent contractor should expect to be able to charge $50/hr and up if he/she is doing the work full-time as a source of income. That sounds like an awful lot, but remember that you'd normally have to provide your own health insurance, IRA and so forth. Obviously, that kind of price is going to sting, and would probably be a deal-breaker in your case -- and unless you're licensing yourself and making this a full-time job, you probably don't have the overhead. There's no reason, though, not to at least treat yourself as a skilled worker even if there is a bit of a smell of doing a favor involved here. You probably shouldn't be dipping below the $20/hr mark, at least for the visible part of your work (even if you feel guilty charging that much and it's all extra money) -- you want to at least give the appearance of being valuable, otherwise the old "my twelve-year-old nephew..." thing will pop up (guaranteed). Make it clear that what you're doing is worth something. It sounds like it's not much more than a couple of days' cumulative work, really, so the total price wouldn't be that steep even if the hourly seems a bit much.
