If one doesn’t want to self-host it one can always go through a service like PikaPods who do in fact have a revenue sharing deal with Actual Budget. And either way, Actual Budget isn’t really an accounting tool for businesses, or did I misunderstand you?
If you’re in the EU you can do bank syncing for free with GoCardless integration. If you’re in the US you need to go with SimpleFIN which costs a small sum and is in a more experimental phase than the GoCardless integration I think. Either way, GoCardless has been working great for me. Actually far better than YNAB which didn’t even support my bank. It’s literally just set up and forget.