As the manager, your biggest responsibility is hiring the
subcontractors who will do the work. Do you know someone that recently
had work performed on their house? Who did they use? Was it done on
time and within budget? Would they use them again.
Drive around neighborhoods you like and find out who's building the
houses. If you have dealt with subcontractors in the past (and you
trust their opinion), get recommendations from them. If your carpenter
recommends an electrician he works with frequently, that's a solid
lead.
Once you get names, you want to learn all you can. Get a list of
references and talk to them. Examine past work in person. Arrange to
meet them on a current job site. When you find subcontractors you
like, start writing down the work quotes. And remember that the low
bidder doesn't necessarily do the best work.
Do you want subcontractors to buy the supplies or do you want to do
it yourself? Materials are going to cost a pro less money because they
have a relationship with suppliers and can get discounts that will not
be available to you. They will also not be able to blame you if a
supplier delivers poor quality items such as warped limber. Remember
that subcontractors will most likely want money up-front if they are
going to buy the materials themselves.
As for financing, you need to choose between getting one loan for
construction and another for your mortgage, or one loan that would
cover both phases. There are advantages and disadvantages to each
type. Construction loans are by nature more elastic. Your chances of
staying on-budget are not very good.
Most building projects will go over the price estimate by 10% or
more, usually due to unforeseen changes in material costs. If you have
a combination construction loan and mortgage, you're locked in on
construction costs. That lack of flexibility might mean you'll have to
return to your bank and take out a second loan with a second set of
closing costs.
When you act as your own general contractor, there are no
guarantees. And no matter how carefully you shop, things can and do go
wrong. Subcontractors disappear. The price of materials goes up. A
company you've paid in advance folds. And then there's the weather. So
be ready for problems and realistic in your expectations.