Bryan wrote:
I will be leaving my Sea Ray 185 parked in my driveway this winter (we're
about 50 to 60 miles north of San Francisco.

What do I need to do to keep it from developing a mold and mildew problem
over the winter?

The boat has snap-in carpet and a boat cover. It will get very little use
during the winter, but might see a day or two on the water.

Any tips for my first winter with a boat will be appreciated.

Unsnap the snap-in carpet and take it out. Follow with any easily
removed seat cushions. Store them in a dry place, (an attached garage
would be OK).
These items tend to attract and hold moisture, so why push the rock up
a steeper hill than you need to?

Rig a canvas cover that will drain water over the edges rather than
allow it to puddle up in the middle. That's the first key, keep the
boat dry.

Make sure there are some good sized vents in the canvas cover. The
second key to avoiding a mildew mess in the spring is to keep the air
circulating.
If you can rig an electrical cord from the house or the garage to the
boat, one of the low wattage heater/dryers would help ensure a dry
environment inside the boat and will stimulate some air movement as the
slightly warmed air will tend to rise.