I really don't trust the stock market and I live off my rents.

You buy something where someone has lived for years and then pull the floor out from under them and tell them they have to move in the middle of a pandemic.And secondly when you turn housing stock into short term rentals you have just created an artificial scarcity in the market for that area.

Conventional retirement accounts are limited to investments confined to the stock market.

I have been working since I was 15 years old and have 2 years of W-2 forms currently as well as a UTMA stock account.

First, it simplifies the construction of ADUs — a critical form of housing stock — in the midst of a severe housing shortage.

If I were to sell the property then for $150k and invest that in stocks and the markets been averaging 6% a year, that's $9k the first year and then more every year.

Aggressive, I know, but I have a stable and highly paid W-2 job, no debt, a sizeable chunk of cash as well as capital in the stock market, and I also don't spend much.Why now, when everything is so expensive?

Often the bar association will put out a very generic stock form that is fill in the blank. 

I am also a stock trader and as we have seen stocks like Tesla and beyond meat some times you have to wait far to long before the dip comes.

This is true if the secured asset is bonds (I believe Justin discusses using tax free bonds in his posts), stocks, life insurance, RE (basically Equity Line of Credit), etc.