This can cause a build-up of tension which get released (materials shift) suddenly making a knocking or cracking sound.  

Might ease the relationship tension but still allow you to make a nice profit.

Just like you can leverage the skills of a contractor or attorney to save you stress you can do the same with management.Of course, I always prefer just doing what you would do for any other tenant and telling him it isn't personal but it is a way to cause family tension and some people don't like that.Do what you need to do to sleep at night and keep your business a business!

Even if it's all in writing, tensions can get high when it's someones home.  

I usually don't have a problem with power lines and actually live next to high tension lines but to me unless you can get the pole moved this is a no. 

That looks good to me, a nice post tension slab.  

The last thing you want is tension between the tenant and PM and you being the outlet for relief.If you have an issue with a PM overcharging, you ought to redefine the scope of the relationship.

We sold it to the (then) current tenant, primarily due to tensions between the partners.

I wonder if anyone would think of post-tensioned slabs as a more recent development that fits into this category.

I do it as I've heard renters having issues with each other because one person has to pay and they are on the hook which could create tension in the house.