This isn't the question you asked, but I'll answer it anyway: I'm not sure this is a wise idea.
Over the past several years, there has been significant growth in the supply of points to the rental market, including some people who assume they will rent out some or most of their points every year for various reasons. The rental market has been robust over the past several years, and it looked like easy money.
I think at least some of those folks either were not around for or forgot what it looked like during the several years of the Great Recession when points were available for the asking, and the next few years could make that look like the good old days. I really hope I'm wrong about that, but I keep reading articles about air travel/hotel demand not recovering to 2019 levels until 2023. There are reasons to believe that domestic leisure travel will recover before business travel, and that helps WDW. But, a good chunk of WDW's market is international, and that will take longer for a whole bunch of reasons.
Over the long run, I think the rental market will be strong more years than not, and if you are thinking in terms of decades, this could be a good strategy. But, you'd need to be prepared to weather periods of low demand where you'll either need to use your points yourself or be prepared to take less for them. If you think you will go two out of every three years, you might be better off looking for a point total that more or less meets that need with some modest banking/borrowing, rather than competing in the rental pool.