Accordeons:
Beautiful machines. It depends on how much you would like to spend. They are VERY expensive, but there is a simple reason for it. It is an investment. You buy ONE for the rest of your life (most of the times) so it LOOKS as if it is expensive. But most of the times it is two times the price of a keyboard, that is old after let's say 5 years!
There are too many elements important (sound chamber, 120 or 96 bass) what you play etc. but I will give you a list now of what are the best accordeons in my opinion:
In order of being best for me:
-Dallape
-Guerrini
-Bugarri Armando
-Hohner
-Weltmeister
-Serennelini
But it is very individualy tasted this list. For others, maybe Moreschi could be the best.
But I do think that Dallape is lonely at the top along with Guerrini and then the others in whatever position you like.
Hope this helps.
Ilija