If you've got a pile of money that you're trying to flip, and you think this guy is able to churn out a GREAT package with a long profitable life-cycle than follow through on the questions 'WRIGHT' posted above with the guy. Otherwise you might want to check flippa or other sites that sell ready made businesses that are profitable. Much less risk and you can extend your own marketing/buzz/relaunch into it.
OR assess the whole project, software functions and see if anything close to it exists. If so, throw up some guru.com/elance.com call outs to see what it would cost to develop something similar, and perhaps take it on in-house.
Starting from SCRATCH can def. be lucrative but there is so much room for error. I'd look for someone that had software already made and was looking for outreach/marketing money/partnerships.
I've launched a fair share of software in-house. Just finished a custom reg cleaner/optimizer software and paid 4K US for an amazing team in Romania to develop it saving me a boatload, and I own it 100%. The idea and final 'product' is but 30-40% of the equation. Packaging, marketing, scaling etc. is the hard part in my experience. I'd have to be seriously blown away by a team/software to invest from scratch, and all of WRIGHTS points would have to be filtered well in order to invest in them, and not simply outsource that shit and keep it for myself/my team.