Thanks for your replys.
My worries were more about not working together in small areas. Fx. If I varnish first, there´ll always be a little bit of varnish left some odd places that is later going to be covered with paint. Noone is pefect and I dont want bubble ups.
So I get the message. One thing or the other and 2pack need 2 pack on top. I will start with the interior and I think I´ll do 1 pack. there are to many troublesome areas that need to be painted slowly. later on the exterior, I dont know. I have a can of 2 pack Hempel polyenamal and I can get another one with a 30% discount... Thats good. So maybe, I´ll mix a blue with a white and get some medium light blue 2 pack exterior.
Just a side note: You can paint 1 pack over 2 pack but you need to use a primer first.