I am a freelancer myself. Due to less bandwidth of time available with me, I am outsourcing this job. I would have happily done the job of changing URLs for $50. It is not rocket science if you know CMS and PHP. Moreover, its $50+ not $50
I assume you have an idea of how many hours work it will be.
How many hours (nett) would it take you to do it and what is the maximum you are prepared to pay for the whole job?
$50+ means very little to me since it is a small minimum amount and no maximum posted.
Are you prepared to pay a deposit to cover costs in case you do a "runner"?