Because all these developments target high-net-worth individuals, sales teams often charge hefty fees to ensure prospects are legitimate. “If you don’t charge anything and you don’t vet, you get what we call ‘speeders’ — since they speed right past the sales gallery,” says Greg Spencer, chief executive of Timbers Resorts, a developer and operator of residence clubs around the globe. His company launched a “guest visit” program in November at Timbers Kiawah, a development on the Atlantic Coast’s Kiawah Island, where guests can stay for $1,200 a night.