Also something to consider is what is the appreciation play looking like? 

I think knowing more numbers, heloc limit, plans and objectives for future goals all should play into "what is best".

nice job I grew up flipping land I love that play still fund land flippers to this day is a niche of lending that I have carved out.. 

The big boys play this as a team sport, so think about what you need to know, who you can get it from and then go find that person.

Together, they have a lot of units in play there and have done very well with long-term rents and mid-term as well.

The STR, if purely an appreciation play,  is speculation to me. 

Selling now avoids capital gains tax and lets you reinvest into a new primary home and a solid rental property, which feels like the safer play given the cash flow challenges and ARM timeline.

Thats going to play a big role in your options i think

Most gulf front investments are mostly appreciation plays unless you do a serious renovation.

If you're aiming for growth and can secure a low-interest mortgage, financing might be the better play.