I’ve been using email aliases for a few years now, but all spam I get is addressed to my main email (which admittedly is readily available on my website). Seems like no one has sold my email address yet

While the disposable cards might not always work, you can always create a regular virtual card and delete/freeze it afterwards. Not sure if there are any limits tho

Not really the same thing, but Revolut has disposable virtual cards that you can use (but it’s a full-fledged bank).

Some apps like MBWay in Portugal also allow you to create these virtual cards, but it requires a Portuguese bank account.

Seems to still be available on F-Droid, but the last update was in 2017. I’ve installed it, but ended up not logging in since it’s targeting an SDK version so old that Android is giving me a bunch of warnings (and it doesn’t even scale to my entire screen, there’s a big black space at the bottom)

I’ve had this “problem” before, and I did not want to use the full Messenger app for privacy reasons as well. I had installed Messenger Lite, but it was discontinued a few weeks ago. I now have Facebook Lite, which also has Messenger, and you get notifications as well. It’s not perfect, but don’t give it too many permissions and you should be mostly fine. Using it in the browser is absolutely terrible, and you would not get push notifications.

I personally use Firefly-III. It is completely self-hosted (there is no cloud version that I know of), and is quite feature-complete. Their data importer allows you to import transactions directly from your bank (check if you bank is supported, but all European banks are), so you don’t need to create anything manually.

For example, I have the data importer running daily, and then I only have to set the correct category for each transaction, which doesn’t take that long.