I understand that after spending more than 182 days in Spain in any calendar
year one is classified as a Spanish resident. As a result, it is necessary
to re-register one's boat as Spanish which costs ~12% of its value. Also, it
is then necessary to get a Spanish sailing qualification ("patron de
yate"?).

Does anyone know if the above is correct and has anyone actually gone
through the process? Given the number of ex-patriots with boats living in
Spain there must be many who haven't, but what (if any) alternatives are
there?

Regards,

Stephen.