I wouldn’t worry about the house your living in, as long as it’s paid off or you are paying the mortgage as agreed you should worry. The same goes for the other houses. Lets say you have 5 houses and you have paid off or are paying on time on 3 of the houses and you stop paying on the other two. They will foreclose on the 2 your not paying on but not the other 3.
If you have a property foreclosed upon, you still owe the money borrowed minus the sales in foreclosure and fees for disposal and interest accrued will be added to the amount owing after the sale.
The lender will then sue you for this amount and for the cost of the court action.
If you lose in court, an enforcement order will be assigned to any and all your assets and unless you pay, you will start losing stuff.