Starter home to second home, do we rent or sell?

[Jake Allen]

Hey, we purchased a fixer upper as our primary in 2017 & have renovated it ever since.  New HVAC, plumbing, electrical, floors, kitchen, baths & added a deck.  It's been great, but our family is growing and could use more space.  The house is a 3/2, built in 1950.  We have a 15 year mortgage with about 7 years left (throwing a bit more on principal each month).  Our payments are around $950 and the local rental rates are near $1500.  We owe around $75k on the loan, but the value is near $250k.  I'm racking my brain, would it be wiser to hold onto our first home & keep it as a rental?  Or sell & throw that money towards our next primary residence?  Ideally avoiding capital gains tax, we've owned it for more than 5 yrs & lived there the whole time.  We've captured a lot of equity over the past few years & I kinda hate to "throw it away" towards another primary residence.  Especially since the market might be turning.  So I guess i'm leaning towards keeping the first property as a rental.  Any advice is appreciated!