+ 1 on what Spook said. The belt should be changed if it is 10 years or older regardless of mileage. Don’t know the exact change interval but probably every 70-90k miles. Which is what the 5 cylinder engines were of that era. The V90 is the same engine with one more cylinder. The water pump is normally changed every other timing belt change.

Expect more maintenance than your 740. Those cars are more complex. They are a hell of a road car though!

Good luck 👍

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Will I buy another Volvo??? We'll see....