In your example they could net zero on the back end when the option to sell is exercised... but made sizable fees throughout the entire process.

We're also in the process of adopting a 10 year old girl from Eastern Europe who has some medical needs and a genetic condition, but not Down syndrome this time.

However, the biggest plus to my day job is the medical benefits.

My current roommate is a medically discharged veteran that currently receives his income from 100% disability for unfortunately getting cancer while in service (But he has been clear of it and in remission for years now, THANK GOD!).

Exercise the Option once the paperwork is completed.

I exercise because the pain of feeling awful is worse than the pain of exercising and the pleasure of feeling good.  

that said, I will definitely crunch my numbers, pay attention, and exercise my voice. 

Yes it can be come a hazard and health and safety issue and a code compliance issue if city cites you for a problem issue, or someone is allergic gets bitten and needs medical attention, maybe a bigger issue. 

If you have to move for work or medical reasons at less than 2 years residency then you can prorate the gain for the time you lived there.  

Typical reasons are loss of job, reduced income from job or business, divorce, death in family, health issues affecting employment, overuse of credit cards, medical bills.