you really don't provide much info but in a nutshell it is possible to structure a contract for tenants to stay or not. all depends on the end game which you never mentioned.

All need a some repair, mostly minor age related wear and tear, but some need a lot and a full rehab on these would be more than the value of the trailer.Anyone done this before? 

I keep seeing people mention that QB ties in with their CPA. 

As mentioned above, it’s actually on the inexpensive side.

Other one built in 1949, Allstate agent initially wrote but when assessor went to see it, he didn't even assess due to property's age and they declined to write the policy.I live in NJ and have 2 more rentals in VA so essentially I have 4 properties (including that 1956 built Baltimore), autos and umbrella (requires all covered properties to be insured with Allstate) all with Allstate so trying to see if anyone has their pre-1950 property with Allstate (which happens to be cheapest overall everytime I try to price shop).If anyone has any other insurance company they can recommend for multi-state situation like me then that will be appreciated.

This adds nearly $11,000 on top of the pile.As mentioned previously, if we were to put in an offer today, there is no way for us to "owner occupy" until next June.

I don't think it is a co-op since the agent hasn't mentioned about any co-op interview and rules. 

I don't do individual appointments anymore for reasons you mentioned above.

I'm very mature for my age, I have learned a lot and will continue to learn, and I am (obviously) incredibly ambitious.

For multi family in Canada is their a house age range you would not touch or has a lot of headaches?