Who must obtain a seller's permit? What does engaged in business mean?ELECTRONIC FILING INFORMATION AND RETURN INSTRUCTIONS (CDTFA-401-INST). Buying a business is an exciting opportunity, but it can involve significant tax implications. Learn what you may be liable for and how to protect yourself. With a reseller permit in Contra Costa Centre , business owners purchase items and resell them without paying sales tax in Contra Costa Centre. County Clerk Recorder - Kristin B. Connelly. This tax does not all go to the state, though. It generally comes down to the buyer and seller to decide who handles it. Traditionally, in the State of California, the seller pays the transfer tax.