If I sold it, can I keep 50% of the gains to pay off some debt accumulated from the renovation and use the other half on a down payment for a larger property?

This is what keeps people stuck in the poverty cycle.Wealth isn't about accumulating things to make you happy.

Your options then are: to refinance the FHA loan into a traditional loan and move the extra equity into another down payment for an FHA, or you can now assume traditional mortgages as you accumulate property.

Regarding how many generations it takes to accumulate wealth: I was surprised to read the statistic (in the Millionaire Next Door) that 80% of wealthy (defined as net worth > $1 million) are first generation wealthy. 

Agree.However from all investors, there's nothing crazier than Microstrategy, this is the only company on earth that's accumulating crypto in their book and having more crypto as collateral.

My brother in law makes great money but always payed his debt first, but for some reason or another he would somehow accumulate more debt and do the same cycle over and over.

While you know how long it had taken me to accumulate my $40k downpay for my first rental property with my salary in Texas?

Whatever happened in the past, did it accumulate to what you wanted?

Why did you accumulate what amounts to just a set of numbers in some computer or spreadsheet?

Do you plan on continuing to move from house hack to house hack on a yearly basis and accumulating that way?