As a tax depreciation item, your signs may be deducted over 5 years. But signage will usually last a lot longer if you take care of it.

Awnings should be cleaned and coated once or twice a year, depending on how close you are to a main highway. Use a mild water-base detergent - not a solvent-based cleaner - with water and a scrub-brush or mop. Rinse, dry, then coat with Armor-All or some other vinyl rejuvenator to keep it looking young.

Banners should be installed with elastic "bungee" cords at all corners to resist wind damage and sagging. Banners can also be cleaned like awnings. Banners should be installed against a solid wall if at all possible, unless you only want them to last a week or two outdoors.

Most metal signs these days are built of aluminum instead of steel, so they last pretty well. A wash-down every year or two should keep it looking pretty good, although the lettering will fade or peel off in five to ten years. By that time, it's better to simply put a new face over the old one than to re-letter.

If the frame is made of wood, it will eventually rot away, unless it's pressure-treated. Old-fashioned plywood signs are rare now; we use a marine-grade plywood with aluminum faces sealed over both sides, and edges caulked and sealed with plastic trim. The aluminum faces are coated with baked-on enamel paint (similar to automotive finish) so these signs are extremely durable.

If you use magnetics you MUST follow this procedure regularly and faithfully: at least once a week, you must remove the magnetics, clean & dry all the mating surfaces, and re-apply them.

Magnetics MUST be stored FLAT when not on the vehicle. Find a flat steel surface such as a large appliance or steel door for this purpose.

Electric Signs will require replacement of lamps, ballast, sockets, etc. over the years as they burn out. Lamps typically last two to five years. A ballast lasts five to 10 years, depending on ambient heat in the box. An electric sign will last a lot longer if it is well built, well ventilated, well drained and engineered to stand up against the weather.

Lexan / polycarbonate plastic faces are best as they are practically bulletproof; old-fashioned acrylics are the poorest as they are very brittle. You can clean the plastic faces with detergent and water - never with alcohol or solvents! Check your sign to be sure it has drain holes underneath, and that they are unclogged. Be sure the face retainers are in place and well fastened, so that the face can't work loose. Be sure all the fasteners are replaced whenever the sign is serviced. Re-paint the sign box when needed, to prevent early rust-out.