I'd strongly advocate not going for a crossbreed like this or paying a dubious breeder for getting what is basically a mix of no reliable background.
No reputable breeder of either of these breeds -- meaning anyone who does the proper health testing for each of these charming breeds -- would allow one of their dogs to go to anyone who would produce such crossbreeds. And anyone who breeds such mixes is not going to be testing for health either, or using dogs bred to a good breed standard, increasing the risks. Thus you stand a very good chance of getting a dog that has all the worst health issues of each breed, just the opposite of the arguments that you get 'hybrid vigour'. Hybrid vigour is only relevant to the first generation of dogs produced by healthy parents that are not carrying genes for all the breed's health problems.
All breeds shed, including the coton, and all breeds need a bath. Likewise there's no such thing as an non-allergenic dog, as people are not allergic to the hair but to the dander -- the skin flakes that all animals (and humans!
) shed daily.
Cavaliers can also be barkers just as can any breed. A calm dog is usually the result of good training and not being left alone all day (thus not getting bored anf then anxious, noisy and destructive)
If you want a mix, I'd suggest going to a reputable rescue and finding a dog that appeals to you -- anyone running a good rescue can tell you whether a dog they have is a barker or not. Those who breed mixes and charge purebred prices -- close to or equal what a reputable, health focused breeder charges -- are laughing all the way to the bank.
There's lots of info on cavaliers in the Library section of this site in cluding an overview of the major health problems in the breed and the things to ask a breeder when searching for a puppy. Have a read through those and you'll know what to look for if you decide on getting a cavalier.
If you feel that's what you want to do, then you are more than welcome to stick around and learn more from people here.
I'd suggest reading far more widely on the problems of crossing purebreds in a haphazard way before you seriously consider taking that direction.
For example:
http://www.netpets.com/dogs/newsroom/crossbreeds1.html
http://www.netpets.com/dogs/newsroom/crossbreeds2.html
http://www.nrta.com/hybridization.html
I'm going to close this thread as this is a subject I don't want discussed further on this forum, which advocates best breeding practices and breeding for health. icon_thumbsup