Liaison interpreting in the Bay Area English/Spanish

We need an interpreter to accompany one of our customers in their sales activities. It is agricultural machinery sales and the interpreter will travel with the sales consultant for 1 day at a time.
Dates have not been set yet, but these will be recurring sales visits. The first visit will probably be in late February.
The visits will be in Northern California, so we are looking for interpreters who live in the Bay Area.
Remote interpreting is not an option.
Please offer your services on a half day and full day basis. Travel expenses will be paid.