Hi Kyler,
I applaud your willingness to pay for help, and it’s certainly possible to do so, depending on your goals.
However, assuming that you’re trying to do the development yourself, people enjoy helping people like you (and showing off their knowledge in the process). That’s why stackoverflow is so successful. You’re clearly self-directed, working on a cool project, and you seem to only want pointers, not somebody to hold your hand and do it all for you. I think if you try posting on answers.ros.org with a clear problem statement, you’ll get good answers at the level that you need. The OSRF devs monitor that site, and a well-written question is likely to get answers and even a discussion. You’re already getting advice from tfoote, who actually wrote the tf code you’ve asked questions about - hard to buy better than that, especially on your budget! Again - don’t feel guilty about this! A lot of people enjoy sharing their knowledge and helping other people out.
(Also, hiring engineers is hard! You’re probably more likely to get professionals to provide guidance by asking on an online forum than by offering the chance to earn a few $$ in a nebulous way. The psychology of motivation is fun.)
If you’re determined to pay, and/or require more involved assistance …
I do contracting work, and my first thought on seeing this was that your proposed project isn’t nearly well-enough defined. This could take me < 1 hour of chatting with you, or an unbounded amount of time coding, depending on what level of help you want, what you’d consider “success” and what you’ve already done. You can certainly find people willing to help with either end of this spectrum, though I’d expect either an agreed-upon hourly rate (whether for answering your calls or for actual coding) or better-scoped implementation with a fixed rate. I’d be uninterested in something of the form “provide answers, and the best one gets $$”, since alternative uses of my time involve a known payout.
You’ll also need to figure out the logistics of $$. If you’re actually hiring somebody, then taxes get fun. I don’t know the legalities of this idea, but I’ve seen an awful lot of one-off things enticing students to help out in exchange for Amazon gift cards.
Good luck, and I look forward to seeing your progress!
Laura