My list was rankings by dollar amount and number closed Nationwide for past four quarters for NON QM lenders that do DSCR.

Not what we are looking to do and all the MLS listings just don't pan out numbers wise so far.That's awesome that you got some returns on flips and found some buy & holds recently. 

The number of calls you make, are only important if you are guaranteed a specific dollar in return per call. 

You won't be forced to de-convert unless you have violations...eventually the city will start fining you.Very critical terms are non-conforming (no violations - grandfathered in) vs. illegal (violations)...

If you have a regarded tax entity, e.g. partnership, S Corp, C Corp, you need complete financials -- P&L and balance sheet to adequately prepare the tax returns and answer tax related questions. 

I'd like to not "find out the hard way" if one of these sites are not a good match for me.The ones I'm considering are Propstream, Property Radar, ListSource, and PropwireSomething to note, I am looking to return to doing some wholesale deals, using criteria such as absentee owner, out of state owner, tax delinquent, vacant, liens, and pre-foreclosure..

If using a lender this is a non issue.

Remaining money (less title fees) in escrow is returned to wholesaler (less PML funds and fee if used) with the remaining from the Step B contract.

I have heard positive things - expect lower overall returns in exchange for them doing the work! 

Commercial zoning would be okay as long as the property is considered LEGAL but non conforming.