Thank you all for the replies, great community! I get, in the end, an account at Migadu.com. The site is simple and nice, the configuration not so complicated (I had to register a domain) and the support was great. I had a problem with mutt and they've solved very quickly (need for mutt-sasl pkg). They've also a config page for Mutt (migadu.com/guides/mutt). The price is fair: only 20 mss/day, but that's all I deserve.
Best regards, Matteo P
