But is this a smart way to begin my real estate journey, with my goal being to retire myself and future wife by 40 with 20 doors.

Most often, from other investors I know that are retiring.

It worked really well for a few years until my property manager retired and I had to find new ones. 

Sounds like you’re navigating a big transition and doing a lot of things right already by planning ahead and speaking with a tax attorneyA few things to consider or ask about when you meet with themCapital Gains Exemption If this was your primary residence for 2 of the past 5 years you may qualify for the Section 121 exclusion which allows you to exclude up to 250K in gains if single or 500K if married filing jointlyCapital Gains Bracket You’re right to look at your taxable income including W2 wages and life insurance proceeds to see where you land The life insurance death benefit itself is generally not taxable but if any of it was interest income it might be Ask the attorney to confirm that partEstimated Taxes If you sell the house and owe tax you may need to make an estimated payment to avoid penalties especially if your W2 job didn’t withhold enough for the yearHealth Insurance and Marketplace Credits Since you’re planning to go on your partner’s plan this may not apply but if for any reason you do end up looking at Marketplace insurance your income level will impact subsidies Ask how your income mix affects thisNew Business Planning Talk about how startup costs might be deducted how to structure the business (LLC S corp etc) and whether making a clean break this year or early next year gives you any tax advantageRetirement Account Planning If you have any traditional retirement accounts and this is a low-income year you might consider a Roth conversion or some other strategy to optimize your tax bracketIt’s totally normal to feel nervous about a big change like this but you’re already doing the most important thing which is planning proactivelyHappy to talk more if you want help organizing the numbers or figuring out what to ask I work with a lot of people going through life and business transitions like this and it’s all about getting the right pieces in place ahead of time

Having built my life around helping everyday “mum and dad inventors” create financial security and guarantee their retirement, I know my way around these markets.

You can EASILY retire with 5 paid off properties in most markets. 10 provide a nice upper middle class living by themselves.

Trying to help them avoid cap gain tax since they’re retired. 

If you do that, you may be able to retire by 35-40.

My parents are retiring in a year and are considering selling their house and buying or renting a place close to me and a place close to my siblings who live in another state.

I've spoken to the contacts on the builder side at rent to retirement.