However, I figured if there was a good credit card with good cash back options, I may as well use that and then pay the bill in full each month while rehabbing.

Just come out and say it, ask them if they would be interested in a cash offer for their home?

Purchase price: $1,730,000 Cash invested: $560,00014,000 SF 11-unit mix-use building consisting of 2 retail spaces and (9) second floor apartment units.

I am always telling people that I buy houses for cash any condition, As well I have a Facebook page that I post weekly to stay relevant and remind people I am looking for houses to buy all the time. 

We have the opportunity to buy four single family homes in Prescott, Arizona that are currently cash flowing.

Purchase price: $40,000 Cash invested: $100,000 Building a duplex from the ground up. 1600 sq ft. 4-2.

Technical point: While you will technically incur "mortgage boot" by not replacing the debt in your new property, using another cash source to replace your debt gives you a "boot offset"; meaning you won't incur tax on the mortgage boot by doing this. 

So I tell them good , bring your buyer by and I will kick in 1% for a full price cash non contingent contract . 

If so, a best course of action would be refinancing those into lower-rate perm debt which should lower monthly payments and maybe provide some cash-out - that would be the cleanest/most conservative way to build up some more capital

That is something cash for keys should be the first thing to do!