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.

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.

Quote from @Christopher Stevens: Investment Info:Single-family residence buy & hold investment.

The other nice benefit of 100% VA disability is that you pay NO PROPERTY TAX on your primary residence.  

My husband and I just moved into our new primary residence about 40 min outside Savannah, GA.

If you've never owned a property or home before, I would probably start with buying a primary residence.

Most work like this: Rates: 9% to 13% (Most Deals are 11-12%)Terms: up to 36 Months (Most Deals are 6-12 months)Fees: 2-4 points(%) of loan amount paid at closing (Most Deals are 3 points(%))Minimum Loan Amount: $50,000 (For loans less than $250,000 $2,500 minimum fee)Max Loan: 65%-70% of After Repair Value(ARV)100% Rehab Financing Available (Require 20% of purchase price down payment or cross-collateral)Closing Timeframe: 48 Hours - 3 Weeks (Most Deals are 2 Weeks)NO PRIMARY RESIDENCES, NON-OWNER OCCUPIED ONLY, BUSINESS AND COMMERCIAL USE ONLY.

The first step I did to raise capital was refinance my primary residence. 

., mix STR with personal use or convert it to a primary residence), depreciation recapture is not triggered immediately but will apply when the property is sold.

It might make the most sense to just sell your primary residence and use it as 40% to 50% down payment on your future home.