years ago i did a lot of tires so i decided to do my rear (240) tire i took it off and to break the beads i put it in a vice. when i tried to take it off the rim the (metz) side walls was so hard two of us could not do it without messing up the rim. the dealer tells me it takes three guys to change it.
if it has a ct because the side walls are thin i would think it would take an expert to unseat the tires.
$ 20 to $ 50 a bargain
if u do it your self u will save about a $1 hour
and i know some one has done it in 5 minutes.