How much equity do you need before you refi

[Dillon Himber]

I bought a house in November my loan amount is 276k and the house just appraised for 290k. I have a 13k second mortgage. I’m not sure if you have to wait a set amount of time or if you need to have a certain percentage of equity to do a refi. My thoughts were to refi so I can pay off the second mortgage then rent out the property because in my mortgage contract it says I’m not allowed to rent out or I have to pay that mortgage back in full