Regarding taxes, you can take a look at CoinTracking. As far as I know, you can also book online consultations there :) Otherwise, every tax advisor should have some idea of the topic by now😅
@Ph1l1pp you can save something with Code Blocktrainer, for example, and if you pay with Bitcoin you get a few more percent :) I think the price for CoinTracking Premium is relatively fair. At least you don't have to worry about the annoying tax issue anymore