I had never heard of a V90 before yesterday but found one in amazing shape that I want to buy. I’ve previously owend a V70, s40, s60, 860, 240DL, etc., and was surprised to learn that the V90 was only produced for one year, 1998. This car has 158,000 miles and the Carfax report is positive. Also, online reviews give this model high marks.
Does anyone have any other information on this car that would be useful in making my decision.
You’ve owned enough Volvo cars to know they are expensive to maintain and repair. The V90 could be hard to find parts, but otherwise should be similar to other Volvos. I sold a '98 V70XC because it was too expensive to keep on the road.
If you can live with repairs bills of $2,000 and up once or twice a year this could be your car.
It wasn’t really produced for only one year. In 1997 Volvo redesignated the old 960 as the V90. I bought a 1998 V90 in September of 1997 and I still drive it every day. This car seems indestrucable. Yes, maintenance runs a bit high (I maintain it very carefully) but it is a LOT cheaper than buying a new car. I will give it up when they pry my cold, dead fingers off the steering wheel! 
Here’s what other owners say about it: