Many don’t go on visits at all - a risk of course. Some go after acceptances and offers are in.
You can do sessions, tours and more on line.
Even schools that track interest understand this. Is it great to see a school? Yes
Must you do b4 applying ? No
Some go after acceptance to those affordable.
Some pick a school sight unseen. Not optimal but happens. Especially if only one makes budget.
Do what’s best for your family.
Good luck.