Thanks for all the advice. To answer everyone questions, the cost of the project is absolutely the best cost around, finding anything cheaper is unrealistic. I know this from getting three different bids from outside contractors, and getting two bids from contractor buddies of mine. Permit fees and utilities is what's really driving up costs.
Prefab is something I haven't considered, but remember this is a built above a two car garage, I don't think that's realistic!
The price of construction in the front range is a whole new animal.
Also, I'm a finish carpenter that's done similar projects. So I have a pretty good handle on costs. Costs have the potential to go down significantly as I will be doing the finish work, but I'm making my assumptions as if I subbed out everything.
Estimating costs by straight square footage is not a good tool for a project of this type, as it really doesn't account for tying in utilities, permit fees, raw water fees, or possibly adding a water tap.
But the good news is that the numbers still work for the project, so I'm still motivated to go forward.
So for financing, I guess the biggest issue is finding a HELOC that offers 90% LTV, which I haven't been able to find. If anyone has any advice there, I'd appreciate it, thanks.