Keep equity for lower mortgage payment on primary v. buy cash-flowing invesements?

[Jon Dawes]

I'm still green around the ears but am preparing for my first rental property purchase this year.

Assume for the sake of this conversation that all of my other finances are in order. I have been trying to process two different scenarios. I am open to other scenarios.

We have access to $200k ish in equity in our primary.

We will soon have access to another $100-150k for retirement/investing/IBC/etc.

I would like to move into my young family into a (new build or fully renovated side by side) duplex. The point is to have the tenant help or fully pay the mortgage.

This is where the question comes in.

Do we, for example, sell our current SFR and put all/most of the equity into a down payment on the duplex and have a lower monthly mortgage payment?

Do we, instead, put as low a down payment as possible (owner occupied financing) and buy several cash flowing REIs to cover as much of the new higher mortgage as possible, using the chunk of equity from the sale of the SFR?

The overall goal is to do the traditional 'stack' over the next 5 years (duplex this year, double the number doors each year for 5 years, a la Multifamily Millionaire).

I do appreciate that every REI property is different and have used many of the existing calculators to do the math, including Rent to Retirement (leaning towards using them) and that it is not easy to get instant thousands per month in cash flow. The idea is to get as much as possible using the equity and pay the rest with our income, with the goal of long term wealth building for financial freedom.

Of course there are probably factors I'm not considering and lots of variables, but hopefully the primary question is clear: keep a lower mortgage on one's primary residence, or use as much equity to get as much cash flowing REI as possible.

Thanks in advance, JD