While you might already have a great upright vacuum for your carpets — and maybe even lightweight cordless vacuum in your closet — a robot vacuum is probably one home appliance you may have hesitated to buy. This is because most are relatively expensive and cost $500 or more, which might make you wonder if it’s really worth it. But if there’s one brand that makes reliable cleaning appliances that last, including vacuums, it’s Shark . One of the brand’s more under-the-radar vacuum models is the