Also, take into account what type of personality your cats have. We have three cats and Anna, who was raised with them, treats them each differently based on their personality.
Simon is laid back and doesn't care--so they hang out and even take naps together. Mia is a spaz and likes to play, so Anna chases her. Alley is lazy and just hangs out...so Anna pretty much ignores her. It's not all on the dog, you need to know your cat as well.
Owning any dog costs money, food, chews, toys, supplies, training and then vet visits. As they get older they cost more...I spend a nice chunk on supplements for my senior. BUT you cannot put a price tag on the love they give you.
Just be prepared for the costs...it might not be a bad idea to go ahead and do research now to find out what kind of food you want to feed and do a yearly cost analysis. Call your vet and get a price guide for the first year of shots/care. And if you're anal retentive like me, put it in a spreadsheet and get an idea of your monthly/yearly costs.
And of course, make sure you have the most important thing for your dog--time.
