The Board of Supervisors will consider sharp cuts to the number of short-term rentals in West Marin next week, while exempting the shorefront communities of Dillon Beach and Seadrift from any caps.  

The proposed regulations, which were approved by the Planning Commission in November, could gradually reduce the total number of S.T.R.s on the market by roughly 40 percent, and in some places by more than 60 percent. County staff originally proposed an 11…