The LL is in the wrong, but you have been minimally harmed (some lost time and effort, maybe application fees).   

There is no harm to have your listing there too just set the limit for your stay.

We don’t know any PMCs to recommend in the area mentioned, but since selecting the wrong PMC is usually more harmful than selecting a bad tenant, you might want to read our series about “How to Screen a PMC Better than a Tenant”:https://www.biggerpockets.com/member-blogs/3094/91877-how-to-screen-a-pmc-better-than-a-tenant-part-1-services-and-processesWe recommend you get management contracts from several PMCs and compare the services they cover and, more importantly, what they each DO NOT cover.

House is habitable on day of close through contractors will be working there.

I wish someone told me this when I first started landlording, but theres a couple of things you should start getting into the habit of.1) Sign a new lease with the tenant when you first acquire the property (assuming they are at will).

Even for a "simple" garage conversion, there may be structural changes needed to make the space habitable.3. 

I’m grateful I didn’t, because I saw in the cancellation policy that they would close all credit they opened for you (which would harm your chances of upping your personal credit limit).

But if the conviction is remote in time (e.g. over 3 years ago) and didn't involve intentional property damage or bodily harm, perhaps the conviction is not sufficient cause. 

My insurance company won’t let me rent my 2 car garage or an office space that I have because it poses a “threat” of a non-tenant person coming onto the property and potentially posing harm to my residential tenants.

If the roach problem pre-existed the tenant moving in, then not only is the landlord in default of the lease for not providing a habitable property, they are also in violation of Maryland law.