I posted an ad for rent and the first 2 calls are from businesses who provide care home or assisted living servicing.

If the company you are waiting on is slow/non-responsive when trying to win your business I wouldn’t expect quality service if you choose to go with them.

Both told me that their department doesn't do environmental studies on properties, and suggested to talk to the Planning & Zoning / Developmental Service.

Have you actually read Section 1954?

I'm looking at what options I have to pull equity out of other rental properties I have.Does anyone know of investor-friendly lenders that service the San Antonio / South Texas area and will allow home equity loans or HELOCs on rental properties?

People do it all the time actually.

To actually answer your question though painting is not hard but you will not get the same results as a pro, and I argue you don't need to. 

My relative actually bought an old church and the two properties next it and fixed it all up. 

This means lots of demo and city services helping bring the area around.

Let me know if I can be of service.