Question about buying a private car in California...?

A couple of things: Although DMV would like you to tranfer the vehicle within 10 days of the date of sale, no penalties will be essed on the transfer fee until after 30 days from the date of sale. You can start a transfer of title without a smog, they just won't complete the process until you do get the smog. I would be more concerned with the registration. If the registration is expired or close to expiring then you'll want to jump on that as those penalties can be significant. Also, be aware that DMV is required to collect tax on the purchase price of the vehicle (that is equal to sales tax in your county)