Some require seasoning and others don't. 

This is called "seasoning."

The duplex was built in 1949, so it is older, and is right around 1050 square feet with the asbestos is only on the exterior siding.

My accountant is a seasoned cpa and works specifically with real estate but is hesitant when it comes to ideas like this when I bring them to him.

He's an older investor who knows he needs to be more liquid at this point in his life. 

Imagine if it was in a vacation destination that was all booked up during the busy season.

Some ideas to help:* Let the tenants know that you know the house isn't well insulated, and you'll compensate them $200 per winter season for the poor insulation

Purchase price: $25,000 Cash invested: $30,000 Sale price: $76,500 Large older brick home in need of medium rehab in all areas.

Trying to find places where the likelihood of being able to rent during off season are high. 

You can even aim for MFH there and turn a duplex or triplex into a cash cow with 2 units as STR's or diversify your streams of rent & stick one long term tenant the to mitigate during slow seasons of Airbnb.