swapping out a cv axle shouldn't take a shop very long at all, provided they have the proper replacement part.. i don't know what the "book rate" would be on a task like that, but i imagine it wouldn't take more than 90 minutes of labor..

as far as a tranny flush & fill goes, that's your call.. if the fluid on the dipstick feels gritty between your fingers or smells burnt, it's time for a change. i think the recommended interval is 30k miles, but i've heard of members doing it every 15k.. one thing to watch out for though.. if the fluid hasn't been purged in awhile, doing a flush might break loose some deposits which have settled and they could wind up clogging other parts of the transmission..

i flushed my tranny and about a year later i lost 3rd and 4th gear.. don't know if they were at all related..

-adam