Not sure what to do with a house with equity and need advice

[Jeremiah H.]

I purchased a SFH for my primary residence about 3 years ago via short sale. Purchase price was 133K, I put down 20% with a 2.99%APR on a 15 year loan. I owe around 90k on it currently and it's worth roughly 180k. We have since moved so it's no longer our primary residence. It rents for $1300/month and is a little under market value.

I'm trying to figure out how to use the equity in the house to purchase additional properties. One issue is losing my 2.99APR if I go through a traditional refi. At this point I would probably end up with a 5% 30 year being as it would be an income property and not primary. 

It's been difficult finding someone to take a second mortgage on it so I can keep the 2.99% on the 90k I owe currently. I've thought about selling it since it's not an ideal rental. If I sell it I assume I would have to pay long term capital gains on the roughly 50k profit or do a 1031. 

Anyone have any ideas on what to do with this property? To this point I've only been doing buy and holds and have yet to sell a house.