Hey Liz,
$3000 sounds very good, maybe a bit too good. I would have the car inspected thoroughly by a Volvo repair shop to see what condition it is in. These cars can have several issues (http://repairpal.com/volvo-s70-2000/common_problems) so it's best to have a clear picture of what your in for.
The maintenance on these is every 7,500 miles, with a major service every 30,000 miles. So it should've had a 90,000 mile service. The upcoming 105,000 is a fairly big service as well (timing belt replacement).
Find all the services and what is done at each, here: http://repairpal.com/estimator?car_type_id=2721