Send boxes back to California?

Anyone know the cheapest takyubin company to send boxes back to SF area?
I remember there's yamato, nippon express in the bay area, has anyone done it?
Also, if I were to willingly pay for the extra luggages on my flight back, how many luggages or boxes can I bring? Would this be cheapest?

How many boxes/how much of a volume are you talking about? If it's a load that requires a moving company, you could call up Yamato for a quote. If you are talking about a few boxes of books and clothing, then you might try the post office and send via surface - it will take a few/several months but that's the cheapest. If you pay for extra baggage on board your flight, I've heard some numbers like 10,000 yen per extra kg, so I would not recommend it in terms of cost efficiency.

In this thread you might find some dat on sending one or a couple boxes thru the post office: http://www.japan-guide.com/forum/quereadisplay.html?0+79937

B. Slager