Should we rehab with the tenants there and seek their corporation?   

(Current rent is 950--market rent is 1400; I will do a renovation (20-25k) and rent to corporate tenants (e.g. travel nurses) for 2200-2500).     

Not likely in the beginning.This is tax season and the corporate tax deadline is in 10 days, Brian's answer is likely the best  you will get before summer.  

Not sure if it is their polite way of rejecting to work with me or if they are just too busy.

My question is what concerns do I have if I repay myself the money I invested in my S corp or can be LLC.

@Don Spafford Running a business through an LLC or not (assuming LLC has not made an election to be taxed as a corp or S corp election) has no bearing whether it's subject to self-employment tax. 

The large corporations and REITs will bring transportation to them in some way or another which will spur the desirability and presumably, value.Ultimately this will be a very long term play for you.

If you take @Kevin L. s proposition, my little 16 SFR business should have PM software, commercial office space, HR, Legal, Marketing and maybe a corporate jet and helicopter. 

Listen politely, and continue with whatever you were going to do anyway. 75k wasn't an arbitrary number thrown out there for no apparent reason.

Furthermore, it is very easy to "pierce the corporate veil" because, presumably, you will be living in the house i.e. you are getting direct benefit from the asset (and the asset protection is in name only).