In my case, I have residential rentals in one LLC, commercial properties in another, self storage in a third, and my real estate company operates in a fourth.

I, like you, am a managing partner of a holding company, but unlike you, we are heavy into the real estate space.

Quote from @Marcos De la Cruz: Thanks for the reply but I'm interested in reviews pertaining to that company and the properties they sell to investors.Not really considering them for PM. 

Could call the title company or transaction coordinator to validate.   

GSP REI is a diversified real estate investment company based in the Philadelphia area.

Does anyone have a company they recommend for HELOCs?

We'd love to have you interview with us at Keller Williams.While I don't think any brokerage publishes numbers, I think we likely have more investor agents than any other company. 

Amy Vaughn continues to serve on the Company's Board of Directors.In 5/21/2021: Director - Amy VaughnAmy Vaughn Serves as a Director.Ms.

Obviously the numbers and location would determine which is the best option for me but these would be my preferred methods. 

Personally, I would never live in PHX, but that is all personal biases (I prefer seasons and greenery), and clearly lots of people choose to live in PHX.At the end of the day, I would argue market selection almost only comes into play when you are talking assets that cater to institutional buyers that have to get investment committee sign off.