Please share your experiences with this type of arrangement.

You're welcome to message me as well to arrange something.

In the current arrangement, where he gives you the deed, he has no right to the future cash flow.  

You can do laddered arrangements 1 million to 30 years, 500 million to 15, etc.  

Contracts to sell and buy houses have contingencies like that, but not rental lease arrangements.- Holding deposit needs to be at least one month rent for you to hold the property for them, and it's non-refundable. - This is a tougher time of year to get a tenant.

Had to chase the definition to understand this one:http://www.investopedia.com/terms/c/contractfordifferences.as:- DEFINITION of 'Contract For Differences - CFD'An arrangement made in a futures contract whereby differences in settlement are made through cash payments, rather than the delivery of physical goods or securities.

Her mortgage likely has a due-on-sale clause which may prevent a subject-to arrangement.  

I'd rather the tenant just contact the property management and make arrangements.

For a $6k repair, it could reasonably take a couple weeks to arrange financing - if my credit is good, schedule a contract, delay, get permits, delay, delay, do the work, etc...! 

You should have never taken $50 off their rent .. should have never give them $50 credit towards their  electricity being out - none of that was your responsibility - especially considering that when you made arrangements for an electrician - they denied him the opportunity to repair the problem - 100% on them.