I am a Realtor and have seen so many people walk into my office in tears, having to sell their properties (short sale, foreclosure, bankruptcy) due to having too much outstanding debt on them and not being able to keep up with the payments.

They will tear you apart. 

Should spell out the security deposit is forfeited, MR done, sent to collections for any make ready repairs outside of normal wear/tear if not paid with X number of days etc.

In Seattle (and the immediate communities), There are deals to be had, but most are turds that have been sitting and are finally becoming attractive due to sheer demand, or properties that are basically tear downs.

Is there a smaller group in one therefore less wear and tear on your property?

You're going to tear your hair out trying to find a hard-money lender and/or seller financing if you don't live in the US. 

Some tenants would even gang up on the landlord and there was a quite of bit of wear and tear in the units every time there was a turn over. 

Is is a reroof or a tear off. 

I am worried the appraisal will be low or the tenants will tear things up lowering the appraisal. 

I'll leave it to others to share any experiences with the building department requiring a tear down.