You should always talk to a mortgage broker or bank first to find how much you qualify for before starting the investor journey.

My first deal looks like it will fall through because the bank doesn't like my work history. (4 months as a union electrician, which the bank considers contract work).

Then your best bet are probably community banks which have more flexibility (albeit worse terms) than larger banks and also worth looking into are DSCR lenders.

If it's worth that much, taking a HELOC on it should not be an issue at all long-term or short-term as long as the bank will do it.

Alternatively, if the bank ( assuming there is a bank) is fine with it, you could negotiate a credit and escrow the funds to be released after you do it yourself.  

Now checkout my Scenario 1 that I just attached the image of.

Contrary to what companies may tell you that charge you $ to get "bank funding".

The location all in,cost him X; he got an appraisal for the bank from CBRE national firmof XX and now the firm who called him mentioned paying XXX.

However I would say those lenders would be more willing than a bank to write the mortgage, and after completion you can refinance it.Overall, its probably easier and better use of your time to just find another house that doesn't require the construction and where the numbers make sense.

I "think" I may have a local bank on board to help me out.