I always wanted a Cavalier when I was younger! They are gorgeous dogs.

Unfortunately "intelligence" doesn't equal "well behaved"...if they aren't given the training and the stimulation (mental and physical) to keep their active minds busy then they will become destructive and naughty. I second Lulu, shelter dogs are put through various behaviour tests, and a lot of them are sent to foster carers until their forever home can be found so the carers would be well aware of any issues the dog may have...just my 2c.

But if this breed is something that you really want and you can justify paying that much money for one then go for it. Desexing is only about $150-$200 depending on the vet/dog so for $2000 I wouldn't really take that into account. If it was a $500 dog then I would...