You need to write up a plan...more work..to see if the numbers are feasable.
If you do the work yourself, you will save lots of money.
1 carpenter is a minimum $50 per man hour. If they are legitimate.
X40 hours...x 4 guys for 4 months....that's an average of 32 grand.
Now add a plumber, and electrician for 20 thousand each......getting my drift.
Actually sit down with a drawing and plan with some subcontractors in your area to get actual numbers.
On top of that, us contractors need to make our profit margins of at least 20% and that is the min...or go out of bis.
Do some homework for your area...I know it is cheaper..only it is a bigger headache and you must have the time. By the way...I'm on my 5th house.

Looking to build the last one all by myself in 5 years...with no mortgage.