I'm going to take the opposite tack from Ryan. I've generally done a lot of my own work, and that does NOT mean hiring " friends" instead of contractors. Time for marketing has never been a problem for me, I don't think there are so many deals out there (that you'll have the resources to do) that take up that much time.
I was even doing my own work when I had a fairly high dollar (salaried) job. I found that my work was DONE RIGHT, and LOOKED BETTER as opposed to what Ryan said. In fact, I'd wager that you'll almost NEVER see a composition shingle roof applied correctly!
Learn what you are capable of doing and learn how to do what you're not. The first time I did a roof (layover, not strip the old one) my buddy in the roofing wholesale business kind of laughed at me. He said " I know you're earning a lot more than $3.00 and hour at your regular job" . At the time (1990) I was making about $55K/year. " Well those w****cks are only making $3.00/hour" .
I said that was true, but that since there would be 6 or more of them that was closer to $20/hour. Some other things to consider:
1. I would only be doing it from 7:00AM to 10:00 and from 4:30PM to 7:00. This way it didn't interfere with either my regular job or family time. Also I would not be;
2. Walking around on a comp roof in the heat of the day, wearing off the material somewhat no matter how carefully I walked on it, and
3. Hired guys are NOT careful walking on your new shingles, the often do not pick up their feet and I've seen them " pivot" on their foot when their co-worker calls to them. Thereby turning a 25 (I don't really think a shingle can last 30) year shingle into a 2 year one!
4. I know it was DONE RIGHT and cleaned up after, ie; no roofing nails left around for my tenant's kids to step on!
BTW, I've never laid carpet, and I only know how to troubleshoot HVAC systems, although I can do the electrical repairs on them, just not the freon related stuff.
all cash