Agreed with Jautor and Joe, and mostly because of your Control4 request. Control4 is dealer installed only. So, essentially, you're asking someone to use their employers' equipment to install your system... and when you need to adjust it, that same person is going to have to do it again.
It's one thing to, for example, ask my Dad to run a few electrical wires in my condo since he's an electrician. It's completely different to ask someone to install a complete A/V and home automation system as "freelance work." IMO, not going to happen. Sorry.
Now... if you're looking to save a few bucks... low voltage wiring is pretty easy, and I bet you can find someone to run all your CAT and speaker wires for cheap (couple hundred dollars for labor, and you buy all the wiring). Electrical work is a little more difficult, but you should be able to find a cheap electrician, maybe even a union guy to do a side job.
HOWEVER, a bad electrical wiring job can create serious problems, so it's best to go with a company that has insurance. And, in fact, you might not be able to find someone to do it as a side job, given the repercussions if he makes a mistake. My Dad will do a side job for me because I'm his son... he won't do it for his neighbors, because if anything goes wrong, he could be liable.
And, is your developer OK with this approach? I had to twist my developer's arm a bit to get him to let me use my own low voltage guy. And he had two conditions: 1, he had to be insured and 2, he had to do in on the developer's schedule.