My suggestion would be to go back to your rental listings, and make a comment that the properties are not for sale. 

A mechanics lein stops my sale if they actually do the work.

I want to start to build my portfolio to a point that I can jump into real estate sales full time but still have some cash flow I can rely on.

1031 exchange from a sale of a rental property plus HELOC to fund the remaining.

There is plenty of good turnkey properties on the MLS for sale that would cashflow using the 1% rule and you wont have to overpay for them on a "promise".

I would imagine the bigger loan origination companies out there who underwrite like robots because they are lining up the sale before closing  will be the exception and require those docs up front. 

Title company processes transaction and finalizes sale.

You need comparable sales BEFORE you spend $175 or the appraisal will come low to your expectations.

You can use any money you want from the sale to pay personal loans. 

The average sale price for Condos in the NYC Metro area is $649,000 in the last 6 months.