> I own three houses
> I could just about manage covering all the expenses
You put literally all your income into non-liquid assets, taking on significant debt to do so. As you said, you had <5% of your income leftover at the end of the years. This is a lot of why you're in such a bind now. Even just held as cash, that money would be available to help you through this difficult time. Investing in an index fund would also have been fine, and would again be available to you now.
Landlording is a tough game. Don't you think?
There seems to be a perception, actually particularly on here, that being a landlord is a gateway to magic free money, and maybe a lack of consideration that it is basically a _job_, working with risky rather illiquid assets.
I kind of thought this belief was a young-person thing, though; I'm a little surprised to see someone my age going all-out on it, because they were presumably around for the great financial crisis, when, ah, bad things happened to a lot of overleveraged amateur landlords.