I own a 2001 Carnival, thats what the Sedonas are called in Sweden, and I really enjoy the car! Ours is the 2,9 tdi and it is a dream to drive. Plenty of room for the kids w. friends, and it is really stable and handles well.
From what I have read in different threads, some people have had less nice experiances from their Kia Sedonas, but I think most of us are very pleased.
A 3 year old Kia Sedona might be a good buy ,but the standard warranty is 3 years.If the warranty has just run out perhaps the car has some problems the seller wants to offload on someone else.Check the mileage and contact the previous owner if possible to confirm.You dont want to buy a car that has been used as a taxi and the mileometer gone round the clock.I have found that parts for kia are expensive and difficult to obtain and I would only buy from a Kia dealer with a warranty included.
ask to borrow it for a weekend first and take it for a couple hundred mile runs - check everything air con / drivability / unusual noises / gears / seating - remove the seats and check that they adjust properly check the sliding doors / check for rust on the boot above where the number plate is / give it a threashing / check for smoke / check the CD player ejects the CD's properly / check the remote locking check the DVD player if fitted / check for fuel consumption eg £30 diesel = about 200 miles --- then check for a price for a timing belt (possible £600 - £800 ) then when your are really sure - buy it you will love it when they work well. also do not get a petrol one get a diesel and I would always get the timing belt done on any car purchased over 40,000 miles unless they can prove they have already done it.. basically if that breaks you throw away the car.