Proper bookkeeping will help keep track of who has what dollar amount invested into the property in case of a buyout or a death.  

Just remember that $70 is the gross number they charge , they have to buy supplies , insurance , tools , vehicle , gas , workmans comp etc . 

But keep in mind that there might be some delays in getting payments started, particularly in the first month or two as inspections are completed and paperwork is processed.

If I keep it and rent it out, I will have around $70K in equity @Guillermo Perez   Just curious on why 70% instead of 75% loan to value? 

Or you could keep it as a rental and eventually refi the second property.

People come here, buy, move away and try to keep the house as a rental.

they'd rather keep it / do nothing with it than sell for less than what they feel entitled to.OK, i'll stop there. 

Keep existing building ($850K appraisal) and build an DADU 2.

Can never learn too much. keep it coming. 

Realistically, one checking account and an accounting system will meet all your needs and keep your business better organized than 7+ bank accounts.If you want to collect bank interest from excess cash, add a savings account.