What I have done in the past is simply do a walk through to make sure the deposit return is warranted (no damage) and this is also a nice chance to peak in for any squeaks and leaks.

I wonder if I have to wait til the 11th to issue the detainer warrant?

USPS/UPS box may not NECESSARILY be a deal-killer, but it warrants further investigation.Visit the person's current job sites, maybe buy them lunch.

If Inwere you I would care less about $300 window and its warrant!

Conventional lenders lend on condos every day, but that they have to be qualified, "warranted"....generally a certain percentage have to be owner occupied, less than 10% owned by any one person/entity, etc. 

Should I be doing a Warrant deed instead ? 

The short term lease though allows you to adjust rents if you feel it's warranted as well. 

Also, A list of things you can inform a tenant that are and are not situations (emergencies and non emergencies) that warrant a phone call at 3am or on weekends.

This warrants one very frank friend to friend conversation and if that doesn't solve the issue your "friend" is violating your lease agreement and exposing you and your property. 

He may not be the cheapest person but I feel he provides enough value in his expertise and workmanship that warrants the price.