Definitely not easy. 

Her incentive to do this is that she'd rather loose $20,000 than the entire $66,000 she has in equity.Clearly, I need to verify the creditworthiness of the buyer, verify that they will in fact be able to refinance, verify they have strong homeowners insurance, walk the property, get title insurance, have lawyers draft the needed documents, and make sure it's all properly recorded and collateralized.

What measures would I take moving forward" - easy, vet everyone better, that is also what I would have done differently.It shouldn't push anyone away, everyone makes mistakes, how we learn and move forward, or don't, is the difference between succeeding and failing.

They are very basic machines so easy to fix.The Airbnb expenses I already account for in the income, however what isn't taken into account is the income taxes on that active income.  

If the collector doesn't provide them, I recommend you figure something out to ensure tenants have an easy way to dispose of garbage before it piles up in your back yard.

Check out your local landlord-tenant laws to make sure you are following proper, legal procedures. 

For an easy numbers example, if you put 4% vacancy costs (this is the number Turner used in the last webinar I attended) into your formula when running the numbers, and the monthly rent is $1,000 and the mortgage itself is $400.

On top of that they are relatively easy to sell, where something like a multi family has a smaller buyer pool.So back to the details..Purchasing my first condo with $30k cash, then another $10k, puts me at $40k total investment, I rent out for $800 a month, after all my costs I'm looking at $450 cash flow per month.

If you are cashflowing now, have a solid tenant pool where it's easy to rent out, your property is almost paid off and you want to build up a rental portfolio why sell?

On top of that they are relatively easy to sell, where something like a multi family has a smaller buyer pool.So back to the details..Purchasing my first condo with $30k cash, then another $10k, puts me at $40k total investment, I rent out for $800 a month, after all my costs I'm looking at $450 cash flow per month.