Will I be the A*hole for telling my best friend she is not welcome in my house?

My best friend (Sarah, 27) and I (f, 28) have known each other for eight years. We’ve been besties since our uni years, and even did a year abroad together. At the time, we thought nothing would be more fun than living together in a country we knew nothing about.

That year abroad is when I really noticed her patterns and realized how much of a cheapskate she can be. For example, I often organized dinners for new friends we met there, but she would get annoyed about how much money I was spending. She’d suggest that it would be better if I just did drinks or snacks instead. First of all, I was hosting with my own money, so I didn’t understand why she was interfering. Secondly, she knows I don’t drink—why would I invite people over just for drinks and snacks? It didn’t make sense. I asked her to relax and told her not to worry since it was my proposal and my expense.

Then, when we were about to leave that country, she decided to host a farewell dinner. She invited her friends, told me I could invite mine too, and then said she’d make a list of everything she bought so we could split the costs equally. That felt weird to me, because normally if I am proposing the splitting idea before deciding a date, not thinking of spending less money after I already decided and invited people. Anyways, I went along with it because it was a nice way to say goodbye to everyone. That gives you an idea of what she’s like financially.

After graduation, she moved to the Netherlands, but she still comes back to the city we studied in (where I still live) to meet her old friends. Every time she visits, she asks to stay with me. I love hosting, so I always say yes. But here’s the thing: whenever she stays at my place, she uses me like an Airbnb. She spends maybe 10% of her time with me, then goes off to see other people. Honestly, now that I think about it, she does this to her other friends too. For example, if she has a seminar in Finland, she’ll stay with a friend there—not to visit them, but just because she needs accommodation.

This wouldn’t be a huge problem if she reciprocated, but she doesn’t. When I visited her in the Netherlands once, she sent me Airbnb links beforehand because she “didn’t have space.” But when I got there, I saw a perfectly good sofa I could have slept on if she’d been more hospitable. I know I can’t force people to have qualities they lack, but I really dislike it when someone expects from others what they would never do themselves.

Now she’s asked again if she can stay at my place. WIBTA if I told her no? (I had a recent bad experience hosting her, but I don't want to get into that detail as it would be tmi).
I don’t think a conversation would change her—people who are this cheap usually don’t see it as a problem, so pointing it out would likely go nowhere. Still, I’d love to hear perspectives on this.