Who to hire, or DIY?
There are pro's paid to look over projects. i.e. supervisors, superintendents, project managers, consultants, etc. If you want more control then you need to think like a person in control, not like a regular joe trying to get work done.
I've had very little luck hiring off craigslist, but I have seen lots of people get it done that way. Its all about your style, but more importantly what are you WILLING TO DO. I put that in all caps because people are willing to say they are willing to do things far more often than they are actually willing to do them.
If you want good people, you will have to go through a lot of not so good people; and some Gawd awful ones.
It cost money to hire pro's to inspect your deals, to put together a non-biased/fact based/line item/complete bid for your project that includes timelines, budgets, scope, materials, and permitting/material order information. It cost money to pay someone to review bids/paperwork to insure the trades you hire are qualified and you are protected if they mess up. It cost money to have someone oversee your project to insure quality, code, property material use/install, collect warranty paperwork, meet inspectors, trades, and insure the safety/security of your project; with your projects best interest in your project. (i.e. not what you demand done even though you are wrong thus allowing you to screw up the project.) It cost money to hire a qualified realtor who will not only know all about your project, have the passion to properly convey it to others, willingness to miss their kids Sat. soccer game, but actually spend their reputation, time, energy, imagination, information, to get your property sold for the highest margins in the shortest time possible.
But, if you knew that all in the beginning and (like a good investor does) buy your deals w/out sacrificing yourself to the "eh, I'll just do that myself to make it a deal" mentality, then you can pay someone to do it all for you. It sounds expensive, and it does cost you some of "your" ROI. BUT...you lose far less often on deals that go south, turn out like crap, sit idle on the market, and so on. You pay for what you get, and if you don't pay anything...well..
Anyway; my advice. Pay a pro until you feel you are one. If you think you can fake it until you make it, well good luck and bless your heart.