What would be the cheapest way to transport a bunch of gifts from San Jose to Salt Lake City?

I'm having a wedding reception in San Jose but I will be flying there. Problem is getting all the gifts back to Salt Lake City in a cost-effective manner.What would be the cheapest way to transport a bunch of gifts from San Jose to Salt Lake City?
the post office, priority shipping. the flat rate boxes are one price regardless of weight.



i ship this way all the time, and the items inside arrive in the same condition as it did when it left my hands 99.9 percent of the time.