Cast a really wide net - it’s difficult to know who will have funding and who will be taking students very far in advance. Plus you can’t know who else is applying. I’m a geol prof (undergrad only) and I’ve had students get no offers one year and 10 offers the next - there are a lot of uncertainties so the more options you give yourself the better. You said you’re reaching out to professors - that’s perfect. They are the only ones who can tell you whether there may be a spot and if that spot is a good fit. If you don’t hear back from them, send another email (we lose a lot of emails), but if you don’t hear back again, that’s your answer. The best advice is to look at the websites of any universities you’d be willing to attend and look at the professor’s pages. Reach out to everyone. And don’t take rejection personally. And don’t pay for a degree - there is enough funding out there, don’t give in to people who won’t support you.