Add all adults to the lease and make them 100% liable for all terms and conditions, regardless of who is paying.You can create a new lease, but adding tenants can be as simple as having them sign the existing one or typing up a short addendum.

Can someone recommend a VERY simple app or software program for analysis and bookkeeping?

This seems simple enough and I could increase my umbrella coverage limits for added protection.

Simple answer, yes she could. 

It is simple math that the market with higher rent growth will surpass the lower rent growth market with time (such as a long term hold).

Flips can be done pretty easily in 7 days if they are simple and as mentioned with planning or a templated plan 7 days is totally doable even for one that needs a ton of work.That being said 1 day seems unrealistic unless they exclude a massive amount of planning before the project which maybe they are.    

Create a simple spreadsheet or written list to compare the features of each and identify the ones that align with your requirements.

think of it as simple arbitrage. 

If you do you will never have trouble finding cash buyers because they will come to you.It is as simple as that!

If you are closing outside a title company, which it sounds like this is the situation that you are in, you would simply need to ask an attorney for a note and deed of trust, (once you have completed your 1st transaction, I would ask your title company for a draft Note and Deed of Trust).Once you execute the Note and Deed of Trust, and have it notarized, you simple take it to your local county clerk to have it recorded, the Deed of Trust will have the mailing address of the lien holder, and the original will be mailed to them in 1-2 weeks.Hope that helps, Dustin