Ask HN: How much would ongoing part-time help cost us?

I run a small non-profit using the internet to make the contemporary art world more transparent and accessible for the public. Thanks in advance for any advice!

I do all the coding for our projects myself, but I'm the director of the organization so it's quite difficult to block out stretches of time when I can focus. Right now we're working in PHP but the plan is to gradually move our projects into Ruby on Rails.

Therefor, I want to work towards hiring a part-time developer who can help me every week for something like 10 or 15 hours. Thus my question: I don't know how much I should budget for that goal.

I'd ideally like it to be a permanent position, rather than something freelance (although it might make sense to have a trial period on a freelance basis). I'd be willing to hire someone remotely from anywhere in the US, or hire someone in Chicago where we are based. Would remote workers command different salaries than local ones? I'm hoping to find someone reasonably connected into programming communities and current standards, someone legitimately professional. I'm entirely self-taught, so I know my code is probably wonky and in places overly complicated. Part of what I want this person to do is to clean things up and modernize them, so it has to be a programmer of decent quality (although ultimately the projects are fairly straightforward).

So: what should I expect to pay (total) for this work? Also, any resources about the best way to find this person and tell that they're the right candidate?

Thanks very much for any help!! Forrest