My rancher is on a riverfront with a high water table. It has always been humid and mildewy. The crawlspace has sheet poly down, underhouse drainage and sump system, gutters directed well away from house. Hydronic baseboard heat, window unit a/c, portable dehumidifier. Moisture persists. Will crawlspace encapsulation fix this? What should I look for in an installer and dehumidifier system offered?