Domestic Medium Hair is a coat description rather than a breed. It covers mixed-ancestry house cats with a fuller tail, toe tufts and a soft undercoat, in every color and pattern. Most weigh between 6 and 14 pounds, and personality depends on the cat's genes, age and history, not on coat length.
On Hilton Head Island, the coat is the main thing to plan around. Warm, humid weather lasts much of the year, so a cat with an undercoat benefits from brushing a few times a week to keep mats and hairballs down, with extra sessions during spring and fall shedding. Most do well as indoor cats in a house or a rental, and meeting a cat in person is the best way to judge whether its temperament fits your home.