Stuck on what to do next…

I currently have a 1 bedroom condo in Boston that rents for $1,700. Over all it is in pretty good shape and monthly expenses + mortgage/HOA by the end of the year come out to around $1,100. So as a rough estimate, it cash flows $600/month. It also is on a highly desirable street in an up and coming area. It includes a parking spot and it's a 1 minute walk to the T. Usually when a condo goes up for sale on this street, it's gone in days, sometimes hours. I'm confident that if I listed it for sale, it would go very quick and I could walk away with $75K towards a 1031 exhange.

Or I could just sit on the cash flow! But the problem is, that’s all it will ever be for the foreseeable future. It is only 50% owner occupied, so I can’t do any cash out refi since 51% would be required. I would like to invest in the next property, but I’m finding myself stuck with a down payment issue since the next one would require 20% down.

I’ve looked into areas in Maine, Worcester MA, and Providence when multis are more affordable and cash flow well. The cons: those areas aren’t in as high demand and the tenants will probably be more of a chore. Pros: I think I could get better cash flow and eventually use the equity towards a second investment property.

Curious to hear peoples’ thoughts on this. I’m faced with potentially exchanging a very good thing for something with a lot of unknowns.