What makes a property expensive in Sarasota? Size matters, of course, and so do luxurious amenities, from custom-designed wine rooms to lavish outdoor spas and kitchens. But there’s one key asset that each of the 20 highest-appraised homes in Sarasota County offers to its fortunate owners: glorious waterfront views. Every one of these (mostly) magnificent mansions enjoys a prime waterfront location. Sixteen look out at the Gulf of Mexico from the offshore keys, and four are perched on the mainland Bayfront.