Need advice local GC rates & Approach for Fixing Up Foreclosure

[Liz Murphy]

Hi - I recently bought a foreclose in Lakes Region (Gilford) that I am planning to rent to my Mom (so not looking to cut corners too severely).  The house has work needs to be done with support beams (rotted) and a lot of rotted siding spots where new wood, insulation and vapor seal need to go up.  It is too hard for the contractors to estimate so they are asking to bill hourly.  

#1 - How do I know what a fair rate is for decent GC's in Lakes region (Is $80/ hour a fair rate?)

#2 - How do I structure this project so I don't get taken advantage of (I won't be on the property every day so won't be seeing their actual hours)

TIA and advice on doing this best way possible!