Do scottish terriers need to be groomed?

i really want a dog, would love a scottish terrier, but i want to know if they have to be groomed by a groomer or if u can just brush/bathe them. Im willing to bathe or brush them, but a groomer might be a little expensive. i had a poodle who used to be groomed, and that was very expensive so i cant afford that with another dog. ALSO DO THEY GET ALONG WITH CATS? i have two cats who kind of dont like dogs, but would adjust as long as the dog doesnt try to hurt them...