’02 Volvo V70XC

I am considering purchasing an ’02 Volvo V70CX wagon. It has 198k miles, but everything else, as far as I can tell, is in top shape. Here’s the problem: the owner says it needs linear shift solenoids replaced. That’s a little beyond my expertise. How much should a reasonable mechanic charge for that service? The asking price is nice, but not if the cost of repair is too high. Thanks.