So for example your rent is $1000 per month and they told you on Feb 21 they wouldn't be moving in that day.

One option is to find a co-signer with W-2 income to help qualify, or you could explore DSCR loans, which focus on the property’s income rather than your personal income.

I wouldn’t be offered a Mortgage at $401 a month because the property is valued more so I will have to pay more monthly right due to its current valued after the forced rehab? 

So I am not going to agree on some.

If not, I most definitely would reach out to the tenant, introduce myself and ask if they are going to be out by the 31st or the 1st, I would communicate  to the tenant as if I know they were told they are expected to leave, otherwise you may find they "do not know" they need to leave even if they actually know they need to leave....In the case they claim they are not aware they need to leave, you would need to follow the laws in the state you purchased the property, usually you can find that info on the states judicial branch or speak with a landlord tenant attorney. 

And my rental cash flow went from only $1500/month to 19k/month profit by taking on more loans and harvesting the equity in some of my properties including my primary.

Work backwards from your $300,000 annual target to monthly say $25,000 per month.  

Originally when they were known as FlipOS, they would split up the interest payments,so I would pay the remaining amount for the month the house was purchased and then the remaining balance on the sale of the home to them.  

I would like to get your recent experiences with rent to retirement - positives and negatives. 

Without any cash it is unlikely unless you can find a 100% seller financed deal (they do exist, I just did one a few months ago).