wrote:
I keep my small sailboat in a marina year-round. Is it customary to tip
or give a present to the marina manager at Christmas? How much?

This is not a marina for the affluent. My boat is only worth about
$1600 and I pay $120 a month for the slip.

Thanks in advance!

Does he drink?
A bottle of hootch might be appropriate at Christmas.
Just don't expect to haul it over to his office in a Muslim cab. :-)