The exception is: When the 2 members are married spouses who reside in a community property state. 

It's a quirk that very few areas of the country have.Both the city and county have their own areas that have Section 8 residents, but the Housing Authorities that handle the programs are different. 

One thing I plan to offset my healthcare costs with is paying off my primary residence. 

The main reason I ask is because that is significantly below primary residence mortgage rates let alone any investment loans, if you can get rates like that I might need to make some changes on my end hahahTo answer your original question, assuming all else is equal long-term fixed rate debt is valuable. 

I think we have the option of taking out a heloc  and begin to invest elsewhere.The other idea , that I was thinking is paying off our primary residence which we owe 425k.

I just acquired one from a PM where they were charging a tenant a resident benefit package and a building protection plan.  

They cited insurance reasons, which could very well be true, but many residents felt it as a big "f you" Now folks from outside the community could argue this was an entitled stance from the residents, to feel they had access to this private land when they didn't, and that on the face is certainly true.

Personally If you like your current residence and hope to stay there long term I would forgo major improvements on my primary and use all investment savings to make you more money and cash flow. 

Normal mortgage rates are in the high 6's now, for a personal residence, and higher for an investment property. 

If you do have to move because of a job, you would be safest (in my opinion, i am not giving legal advice or financial advice), i would sell that property to ensure that you did not just purchase with the goal of moving out early and taking advantage of lower rates and lower down payments for purchasing your home as a primary residence.