If you have a lot of equity or if you bought the property when your credit score wasn't great (leading to a high interest rate), then it might make sense. 

You are likely blending PMLs with HMLs here, most PMLs lend on a relationship basis and most HMLs underwrite the credit profile and risk of a deal. 

@Jaycee Greene I’ve contacted big banks small local banks and I haven’t quite tried credit unions although I have 2 credit unions for which I have accounts (but my experience is that they aren’t offering that much better terms).

Currently my credit is under 515, I know I can fix it but need more income and cash.

Also, I have helped build my oldest son‘s credit where he can get a loan. 

Because if I use my credit card to pay for a pizza, I pay a $0.00 fee. 

You might check with smaller outfits too like Co/Lab lending, Preferred Mortgage, Aceland Mortgage, and co-ops/credit unions.

Would be interesting to hear experiences others have had..The expectation for rent being used to help build credit has slowly grown over the years.

They're good to have open access to capital/cash/equity to a property ahead of time so you can execute a deal or purchase when the time comes on a split second decision (versus having to apply to a loan at that time which might take 20-45 days to get approved/closed/etc plus by that time you dont know what your future income/credit/assets will be like in order to qualify anyway).The second use is sleep at night factor and having a reserve of capital in the event an emergency event occurs in life.For these two reasons is why I use lines of credit.

Credit, Criminal, and eviction seemed fine.