Do I need to get receipts from the contractors or will my cancelled checks be good enough for the IRS?

We talked to several banks and found one very large bank that would rap the rehab with the mortgage the problem with this bank is they were very difficult to work with especially for the contractors.

I just received numbers from trusted local contractor so I would like some assistance with reviewing the numbers. 

The contractor I used on my last project wanted $11,000 to install a new 3 ton heat pump (brand new system, new compressor, air handler, run duct, etc) in this house.  

In the classic lemons-into-lemonade turnaround, my income as a W-2 contractor was higher than the salary I could have made as a W-2 employee, which allowed me to build my wealth that much faster.

You did not specify electric or gas or the size of the unit by I use them often because:-For smaller units they are cheaper and easy to install-Take up very little space-Are efficientThe negatives:-May require a breaker reconfigure as the usually require 2 30amp breakers-In bigger properties with a long run say to the other side of the house, it takes a minute or 2 to heat up

I have many local contractor contacts and my brother-in-law is the CEO for Richmond. 

If you have any recommendation for Architect, contractor, Engineer that will be great.Thanks,Tal 

Due to the specialization of the plumbing and electrical, etc, I will have an above average outlay in cash compare to office/retail space. 

It already has electric, but it's off the main house meter,  If I do a submeter then we have to read it and calculate each bill, which is hard for tenants.