Domestic Long Hair isn't a breed. It's the label used for mixed-ancestry cats with a medium-to-long coat, the fluffy counterpart of the Domestic Short Hair. They come in every color and pattern, from tabby and calico to solid black, smoke and bicolor, and some resemble a Maine Coon or Persian without sharing that ancestry.
Because there's no breed standard, size, coat texture and personality vary from cat to cat. Most adults weigh 8 to 15 pounds, and the coat needs regular brushing to prevent mats and hairballs. Where many homes are condos, townhomes and apartments, as they are in Irvine, that grooming routine, a cool resting spot for warm afternoons and a little daily play are the main things to plan for. Each cat's own personality tells you more than the label does.