@Michael S. whatever you choose to do I sure hope you consult with an attorney and have your contractor sign a clearly stated operating agreement outlining the work expected, deadlines for said work and payment schedule based on checks and balances from you also outlying your obligations as well. 

Because once foundation work begins...too many cans of worms and your numbers are way too tight.

I suggest you make sure you keep a tight budget on both your businesses and your personal finances.  

If you don't have access to ready cash, then I would definitely have reserves to cover you when things get tight.  

Im not sure its all FoxxCon. in my market, my own homes ARV Has risen dramatically, I purchased in December for $110K (needed $20K rehab) with ARV of $170K today I could list at $199K and possibly have it bid above that, supply is tight in many markets, and in my opinion we may be on the cusp of the Euphoria segment of the cycle hitting is in spring of next year, Projections I have read from WRA and Zillow show expected price appreciation in my market north of 9% by this time next year.

For most national intermediaries there's a pretty tight range around $750 - $1,000 for a garden variety exchange. 

You have to be somewhat 'seasoned' to do this as you are on a deadline to decide and if you miss something and go firm, you open yourself up to a world of problems.I personally don't do this but there those that do.Good luck,Oren

At what point can we change the locks and throw stuff in the dumpster  if doesn’t get out before a final deadline this Sunday?  

You can invest that cash as you please, including putting it back into real estate if you wish, without the time deadlines associated with 1031 exchanges.

You might be able to keep some of the security deposit, but this depends on your lease agreement and other important factors and deadlines.