Sausalito
There are three nice hotels right in downtown Sausalito (near the water) within walking distance to the venue that we recommend:
Casa Madrona Hotel & Spa, 801 Bridgeway, Sausalito, CA 94965.
Hotel Sausalito, 16 El Portal, Sausalito, CA 94965.
The Gables Inn, 62 Princess St, CA 94965.
A short drive away (about 10-20 minutes) and at a slightly cheaper rate, are two other hotels we recommend:
Holiday Inn Express, 160 Shoreline Highway, Mill Valley, CA.
Embassy Suites Hotel San Rafael-Marin County Conference Center, 101 McInnis Parkway, San Rafael, CA
There are plenty of great hotel options in San Francisco, which is only about 15 minutes away. Just keep in mind that traffic can be a big issue on weekends, as tourists make their way back and forth across the Golden Gate Bridge.
Finally, home-sharing sites like Airbnb and VRBO have houses, condos, and houseboats available in Sausalito for the weekend. Many of the listings will have say they have 30-night minimums for legal reasons, but word on the street is that the owners will probably make exceptions to that if you reach out and ask.
We'd suggest treading carefully with short-term rentals in San Francisco, as the city is currently in litigation with Airbnb.
801 Bridgeway, Sausalito, CA 94965
Centrally located in downtown Sausalito. 10 minute walk/5 minute drive from the wedding venue.
16 El Portal (off of Bridgeway) Sausalito, CA
Centrally located in downtown Sausalito. 10 minute walk/5 minute drive from the venue.
62 Princess Street Sausalito, CA 94965
Centrally located in downtown Sausalito. 15 minute walk/5 minute drive from the venue.
160 Shoreline Avenue Mill Valley, CA 94941
Just outside Sausalito in Mill Valley. 10 minute drive to the venue.
101 McInnis Parkway, San Rafael, California
20 minute drive from the venue.
VRBO
There are some great options here but they go fast so make sure to book early. If you see a 30-night minimum, ask the owner if they can make an exception.