Refi lending options in Houston, Tx? Co-Signer or no?

[Bryce Axelrad]

Hello BP this is my first post! 

I recently all-cash purchased a home in Pasadena,TX. This is my first purchase and I do not have a good W2. I am looking for a good fixed rate option for a loan. I have heard this can be done off of cash flow or assets. I am not sure if this helps but the PP was 80k and with 15k reno it should appraise around 140-155k. Rents in that area for the sqft go at 1300$. With expenses but without a loan it has a 10% cap rate.  

I purchased with private credit I am looking to do a refi to pay back the private line. I am finding it difficult to do a conventional 30 year fix rate without a good W2 so I am looking a private lending options. Also, I have the option of getting a co-signer but I am wondering if that will hurt my portfolio's credentials in terms of banks in the future? At worse case I can flip this property for cash but I really want to start building my portfolio. I greatly appreciate any advice! 

-Bryce