I had trouble finding a bank that would do two dwellings and ended up with a loan requiring 25% down and a few upfront points with 7.5-8% interest rate depending on lock in day.

yes you need to give 90 days. why not have the current owner provide the notice now?

The site prep can vary wildly using your terms depending on what is needed. 

Depending on the total square footage of the residential vs commercial space, you will be between a full commercial lender or a wholesale investment lender that can dabble in the mixed-use space.

@James Martin - Have you considered working with a dedicated virtual assistant who can learn your processes and provide general admin support? 

This is something I am happy to provide to my clients.

It’s really contract dependent.

They can help provide the capital, and you can manage the property.

If you don't mind, please provide advice on house rules, finding roommates, and payment.

Hopefully she provides the receipt but if not you got sufficient discount to be acceptable.This is not a big enough expense to be bothered by.