| General Contractors in Preston, MD (8) | Churches in Preston, MD (5) |
| General Crop Farm in Preston, MD (5) | Beauty Salons in Preston, MD (4) |
| Clergy in Preston, MD (4) | Grocery - Retail in Preston, MD (4) |
| Automobile Body - Repairing & Painting in Preston, MD (3) | Grain - Dealers (Wholesale) in Preston, MD (3) |
| Painters in Preston, MD (3) | Painting Contractors in Preston, MD (3) |
| Real Estate in Preston, MD (3) | Retreat Houses in Preston, MD (3) |
| Trucking - Motor Freight in Preston, MD (3) | Accounting & Bookkeeping in Preston, MD (2) |
| Acoustical Materials in Preston, MD (2) | Beauty Shop in Preston, MD (2) |
| Bonds - Bail in Preston, MD (2) | Business Construction Services in Preston, MD (2) |
| Business Consulting Services in Preston, MD (2) | Child Day Care Services in Preston, MD (2) |
| Dentists in Preston, MD (2) | Excavating Contractors in Preston, MD (2) |
| Florists - Retail in Preston, MD (2) | Fruits & Vegetables - Wholesale in Preston, MD (2) |
| General Construction in Preston, MD (2) | Government Offices in Preston, MD (2) |
| Heating Contractors in Preston, MD (2) | Home Builders in Preston, MD (2) |
| Home Contractor in Preston, MD (2) | Landscape Contractors in Preston, MD (2) |
| Pest Control in Preston, MD (2) | Plumbing Contractors & Plumbers in Preston, MD (2) |
| Potato Farm in Preston, MD (2) | Schools in Preston, MD (2) |
| Tree Service in Preston, MD (2) | Trucking Hauling Contractor in Preston, MD (2) |
| Watermelon & Sweet Potato Farmer in Preston, MD (2) | Welding in Preston, MD (2) |
| Air Conditioning Contractors & Systems in Preston, MD (1) | Airport Transportation Service in Preston, MD (1) |
| Animal Services in Preston, MD (1) | Antiques - Dealers in Preston, MD (1) |
| Appliances - Household - Small - Dealers in Preston, MD (1) | Attorneys & Lawyers in Preston, MD (1) |
| Auto Body Repair Painting in Preston, MD (1) | Automobile Dealers - New Cars in Preston, MD (1) |
| Automobile Detail & Clean - Up Service in Preston, MD (1) | Automobile Parts - Used & Rebuilt in Preston, MD (1) |
| Automobile Repairing & Service in Preston, MD (1) | Automotive Repair & Service in Preston, MD (1) |
| Barbers in Preston, MD (1) | Beauty Shop in Preston, MD (1) |
| Boat Covers Tops & Upholstery in Preston, MD (1) | Building Contractors in Preston, MD (1) |
| Buildings - Portable in Preston, MD (1) | Buses - Charter & Rental in Preston, MD (1) |
| Carpentry Contractor in Preston, MD (1) | Carpet & Rug Cleaners in Preston, MD (1) |
| Carpet Upholstery Cleaning in Preston, MD (1) | Cash Grains Farm in Preston, MD (1) |
| Caterers in Preston, MD (1) | Cattle Ranching in Preston, MD (1) |
| Chicken Farm in Preston, MD (1) | Child Day Care Services in Preston, MD (1) |
| Clubs in Preston, MD (1) | Commercial Fisherman in Preston, MD (1) |
| Computer & Equipment Dealers in Preston, MD (1) | Computer Training in Preston, MD (1) |
| Computers - System Designers & Consultants in Preston, MD (1) | Computers Software in Preston, MD (1) |
| Consignment Shops in Preston, MD (1) | Construction Consulting & Engineering Services in Preston, MD (1) |
| Convenience Stores in Preston, MD (1) | Delivery Service in Preston, MD (1) |
| Distribution Services in Preston, MD (1) | Driving Instruction in Preston, MD (1) |
| Electrical Contractor in Preston, MD (1) | Farms in Preston, MD (1) |
| Fast Food Diner Restaurant in Preston, MD (1) | Feed Store & Farm in Preston, MD (1) |
| Fencing Contractors in Preston, MD (1) | Fire Departments in Preston, MD (1) |
| Food Brokers in Preston, MD (1) | Foods in Preston, MD (1) |
| Foods - Carry Out in Preston, MD (1) | General Merchandise - Retail in Preston, MD (1) |
| Gifts Shop in Preston, MD (1) | Government - Forestry Services in Preston, MD (1) |
| Grocery Stores in Preston, MD (1) | Gutters & Downspouts in Preston, MD (1) |
| Heating Equipment & Systems - Repair in Preston, MD (1) | Heavy Equipment Repair & Mfg Mechanical Equipment in Preston, MD (1) |
| Holding Companies (Bank) in Preston, MD (1) | Hotel & Motel Management in Preston, MD (1) |
| House Construction Contractors in Preston, MD (1) | Hunting Equipment & Supplies in Preston, MD (1) |
| Ice Cream Parlors in Preston, MD (1) | Insurance in Preston, MD (1) |
| Irrigation Systems & Equipment (Whol) in Preston, MD (1) | Landscape Services in Preston, MD (1) |
