Here's a viable option....
Drive one of the working cars out to California - leave it there and fly to Sun Valley Idaho - buy my transporter (bring $180K in cash) - drive it to Texas - pick up three cars and take them to California - turn around and go get the other three - leave all of them and the transporter in California. Fly back to Texas and drive the last one out. Done.
I've done this type of "move" a couple times so I know it can be done.
Since you ask about moving "7 - 8" -- but only list 7 - I'm making the assumption you don't know how many cars you have so I stretched to make 8 work.
