I talked to my mortgage broker and he says I may be able to use the building's equity (he estimated $70K in equity, that the building should be worth $120K based on the monthly gross income). 

If they do, then to close on time you and the seller are very quickly going to have to agree to whatever the lender wants in exchange for being willing to doing an escrow holdback at all, which fancy language aside is basically ransom money in an amount greater than the estimated completion cost, to be released once it's complete (ransoms only work if the thing held ransom is worth more than the thing you want).

I purchased a duplex for 80k and it’s worth about 140k, conventional loan, 25% down.We then got a HELOC on our residence for $68k.

It’ll be worth your while.

I'm not sure what the property is but it is also worth looking into the abandoned building tax credit and state historic tax credits.  

As a landlord my time in the eyes of the court is worth nothing.

LolRemmington financial was the mother of this .. great American greed espisode.. really shows how the pump and dump due diligence scam lenders work in real time.. worth watching. 

But if you have a bunch of money burning a whole in your pocket and you just want to hit the easy button, I think it probably would be worth it to join that training program.

It is $4,000 worth of work and materialsAny suggestions would be appreciated!

Most GC's are not interested in 203k jobs that are smaller as they just aren't worth the paperwork.