MainStay Solutions, Inc. Computer Consultants MainStay Solutions, Inc. Visit Website 3737 Lake Ave. Fort Wayne, IN 46805 (260) 486-8100 (260) 490-0123 (fax) LinkedIn Facebook Hours: 24/7/365 About Map About Information Technology. Consult, Engineer, Implement, Support. Directions On Lake Ave. Large two story building. MainStay Company Vehicles in Parking Lot.