I then connect them with a trusted realtor since we do not have in-house.

So I don't want to spend $90K on a down payment and closing costs and only have $25K to fix it up.

But, for instance, I sent them a notice of rent increase effective February 1 and needed them to confirm that they have accepted the new payment terms through our electronic payment system, and even after repeated notices, they are not responding.

Quote from @Jimmy Rojas: Thanks for the reply, i think it may not be worth it after all, may I ask did you use a calculation app to come up with the mostly payments, if so, care to share it with me.One more thing.

They already have a track record (good or bad) with you, so you can decide based on payment history, inspections, etc.

So my inclination is to compromise her 50% request payment to 25% as stated by Mark and Martin. 

Some people make 4x the rent but squander their income on eating out, drinking, car payments, etc.

Even if their Renters Insurance company wanted your insurance info, an insurance represetnative would be contacting you for it.7) You haven't stated if the tenant is current on their rent or withhold rent payments?

Can I get a loan for the down payment / construction costs2.

Put in your down payment and terms  in the calculator.