BY ADRIANA HERNANDEZDaily Post Staff Writer San Carlos officials are looking at placing a half-cent sales tax measure on the November ballot to help pay for its plans for downtown and cover a possible budget shortfall. If voters reject the tax increase, one of the things the city may cut is funding for the Sheriff’s Office. The city may have a budget deficit estimated between $500,000 to $1 million annually over the next 10 years, and a tax meas…