If so, it might slightly diminish value, depending on how much work it would be to tear the carpets (etc) out and make it a functional garage again.

Gently speaking I think we are reaching diminishing returns.Focusing on the problem at hand the group has generated several viable options that her brother can explore.I would say that keeping it civil with the landlord and avoiding legal threats will probably help get to a solution faster assuming the landlord is a decent person.

Coincidently this is also the time manpower diminished and the project came to a crawl.

And it will increase your credibility instead of diminishing it.

If you buy, rent out and hold for 3-5 years, then sell for profit, the probability that the 50% rule will apply to your properties is diminished because 3-5 years is not enough time for things to go wrong that would have otherwise gone wrong if you hold a house for say 15-20 years.

As houses get scarce, build quality and quantity diminish, people are going to ripe about every little issue.

What I call endorsement of a product that changed my life you call spin... because you are not having the same experience as I am doesn't diminish my experience... it is my reality...

The father is in poor health and wants to sell the house soon, so as to leave his wife with zero responsibilities regarding maintaining their house as his health diminishes.

Once you start monkeying with the system, you start diminishing the benefits of compounded tax sheltering over time that a retirement plan provides.Speak with self-directed IRA providers about how such a tool can be used to generate tax sheltered wealth. 

Of course, be very professional in all of this so as to not diminish your personal brand in the eyes of the seller, but this is a very appropriate and common method.