Check ARV "after repair value" on other duplex's in the area to figure out what it can be refinanced for, consult your agent to pull Duplex comps from MLS or use Zillow and check recent sales, figure out the repair costs https://www.biggerpockets.com/store/flipping-and-estimating-bundle-ultimate and get 2-3 contractors through the space.       

That being said, I am happily committed to an agent who has tons of experience in the Boston market as well as the multi family space.

Now, every year we review the rents and set new rates for all the spaces.

We also have a few micro warehouse projects on our board  (1-3 acre small unit flex spaces).    

.- Garage/Backyard: Yard is standard Chicago size with above ground pool that takes up most space (girlfriend wants to keep, I want to get rid of haha).

I hate the SF rent by room model as an investment because it devalues your own personal space.

I checked in the crawl space and I see a few joists are rotten and need repair.

To build off Mindy's point, there is an Option 3 here and that's invest IN debt :)Might not be worthwhile until you learn more about the real estate space and get a deal or two like that under your belt, but just to give the thread more perspective, investing in mortgage notes could be a worthwhile fit for a similar situation.

On unemployment because of corona, work in event spaces with crowds in NYC so not sure when I'll be allowed to work again.

You make enough money at your main income so that you're willing to work a second job, and pay your employer for the privilege, because you think you have a chance for your own parking space and a promotion...which would mean more work on your part, but...