We have a 2000 Buick Park Avenue Ultra with 90K original miles and it’s a dreamboat. Full leather interior, heated seats and all the goodies - the Ultra edition has a supercharged V6 which gets 20+ mpg and scares rice rockets.
They stopped making that model in 2005, but nice ones can be bought for under 5K.
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I’d like to know where.
We bought ours 5 years ago from a dealership in Albany, Oregon which is 200 miles south of here. It had 77K miles and I paid 6 grand. Try cars.com and punch in what you are looking for - some are more than 5 grand but there are many in that range.