I am trying to find the best software solution to help me set-up and manage a small handful of rent-to-own single-unit residential properties (some are SFH, some are mobile-homes, all include some amount of land).

One thing I was told, which I have never heard of, that when the closing date says "On or About - DATE", that gives them the ability to push beyond the date with no penalty? 

what impact are you seeing on rv park and mobile home park vacancies currently and in the future.

Just like a date of birth, last address and landlord, and employer and income.

Note the date and purpose.

I own a few mobile homes and looking to purchase a MHP before end of year.

Then shop that specific property with your specific closing date around to the banks and they will be much more willing to negotiate rates and terms. 

Usually charging 1% a month with a maturity date of a year.

@Susan Kim-Laubach, from the date of your sale you have 45 days to identify your potential replacement properties (there's some rules to that as well). 

If tenants have not provided rent and/or deposit with terms of lease prior to start of lease date, then you may not be obligated to allow them to move in.If you allow them to move in and they cannot pay the rent then you may end up not collecting for 3 to 6 months or longer.I would have them resubmit an application for May 1st and evaluate based on the new application.