Capital gains tax rates?

[C Price]

In 2020 my wife and I plan to test retirement by living off our rental properties. I'll be quitting my 20 hour/wk day job because I think we now have the cash flow to retire. Our income (including wife) will be dropping a lot, from about $110k AGI to maybe $50K from rentals only. We may still dabble in W-2 work, but we're unsure how much. We'd like to qualify for a healthcare subsidy and sell a house capital gains free wihle we're testing our early retirement. We're 40, if that helps. 

The question: We have a property we own outright. It's a small house worth about $140K. My capital gain on it has been about $50k in 2 years (foreclosure). If my income is low enough (married filing jointly) in 2020, can I expect to pay zero capital gains taxes? I saw a 2019 chart that said we needed to make under $78K to avoid tax. Am I understanding this correctly? 

Thanks!