Quote from @Hunter Hanlon Taylor: Investment Info:Single-family residence buy & hold investment.

I've got about $525K in equity in the property, but lenders have told me that I cannot get a HELOC to access that equity for additional purchases because the duplex was financed as an investment - they have said TX law dictates that HELOC can only be used on primary residences.

Your lease probably specifies the residents must comply with "quiet enjoyment" of the property. 

Don't grill me too hard.I own three rental properties, one is my primary residence with an apartment (5 units total between 3 properties: 1 airbnb, 2 medium term healthcare leases, and 2 long-term rentals).

For the son to qualify for the $250k exclusion, I believe he would most likely need to meet the ownership and use test, meaning he needs to own and live in the home as his primary residence for at least two of the last five years before the sale.

If it became necessary to evict a resident for another reason, unpaid rent is usually a pretty clear lease violation.

Investment Info:Single-family residence buy & hold investment.

HELOCs are fine, but keep in mind that you really only want to use 50 percent of less (each) of your available equity just so you aren't creating a problem that you can't solve later if the value of your personal residences fluctuates.If you both have W2 jobs though, have you looked into getting qualified together and just getting a loan, 10 percent down each?

I'm very new to investing and weighing which options would benefit me the most.Option 1:  Use the cash as down payment on another primary residence and rent out the current.

It was my primary residence for two years before I turned it into an investment property.