In addition to wholesale reps (like Pepco), there is a subset of reps called a "Spec Rep". These reps sell more technically involved products that are often designed and engineered specifically to a specific job. Spec reps have a heavy influence in the design of these jobs to specific buildings and represent a wide variety of products that are applicable to any given project. The primary difference between wholesale reps and spec reps is that a spec rep will sell directly to the end user or contractor, but a wholesale rep will only sell to wholesale distributors.
Reps represent a cost effective variable cost for manufacturers to go to market. There is little risk for a manufactuere as reps only get paid if they sell product. The %-of-sale model means that the rep expenditure is always a percentage of sales and is fairly recession-proof. Finally, reps are dedicated to their local markets, and have relationships and local expertise that manufacturers cannot duplicate with their own staff. Reps offer the best ROI on a manufacturer's possible expenditures on a sales force and maintain themselves as a dominant go-to-market strategy in todays plumbing, pvf, HVAC and related markets.
The Association of Independent Manufacturers'/ Representatives, Inc. (AIM/R) is a trade association of independent sales representatives in the plumbing, HVAC/R, kitchen/bath, waterworks, irrigation and related industries. AIM/R members are the top agencies in the industry.