Here is my situation.

I have

1. Cash reserve 6 month- $35K

2. I maxing out my 401k yearly

3. Roth IRA and Trad. IRA maxed out yearly.

4. Enough money in the brokerage account.

For rental. It has been rented out without a break for the last 15 years. Hopefully stable for another 5-10 years or more. Rent is about $2900 for both sides. When I had an old mortgage the mortgage payment was $1375. Property tax is about $500 per month. Maybe another $150 per month for maintenance expenses. So let make a total of $2000 for easy calculations. For the primary, the monthly payment is $650. I was paying an extra $50. So $700.

My line of thought was either take $100K and put it in a brokerage account but in the current market, I'm concerned to put all of that at once. Another way, pay off the primary mortgage and add the $700 to the monthly contribution amount to the brokerage account. The 2nd option gives me a more gradual path and of course the feeling of not having the mortgage. the 3rd option could just to take that $100K and put it back into principal of the new loan but at 3% and just 15 years term, that just does not sounds right.

Any thoughts?