Advertising costs can strain your budget, but you can gain a lot more advertising real estate for less money by using remnant ads, also known as stand-by advertising. Various media outlets often have more advertising inventory than they can possibly sell, so they end up with advertising gaps in their publications or broadcasts. As a result, they stand to lose advertising revenue and have to develop additional filler material.

By being in the right place at the right time with a suitable ad, you can scoop up these remnants at a fraction of the standard advertising rates. A Detroit newspaper recently quoted the following rates for an ad in the Sunday paper:

• Quarter page: $3,500 standard, $1,300 remnant

• Half page: $7,000 standard, $2,500 remnant

• Full page: $14,000 standard, $4,000 remnant

Who offers remnant ad space?

Just about everywhere you see advertisements, you can find opportunities for running remnant ads:

• Newspapers: Because most newspapers are daily publications, they offer the most opportunities for remnant ads, particularly smaller ads. Space is often available for quarter- to full-page ads.

• Magazines: National magazines often publish a regional edition with space for a certain number of regional ads. If that space isn't sold or an advertiser backs out, it leaves space for a remnant ad. Smaller, local magazines may also find themselves in situations in which they can't sell all of their advertising spots or a client backs out at the last minute.

• Radio stations: In order to remain profitable, radio stations must fill a specific amount of broadcast time with advertising. You may be able to pick up open advertising slots for 25 to 75 percent of the going rates.

• TV stations: The shear number of TV stations available via network, cable, and satellite has dramatically increased the amount of advertising space available. Filling this space is a real challenge.

  You may be able to obtain valuable TV advertising for up to 90-percent discounts.

Prepare your ad in advance.

To take advantage of remnant advertising, your ad needs to be ready to run at a moment's notice. Newspapers often fill unfilled space with self-promotional ads that generate no revenue. In many cases, you can purchase this space for a third to a half of the standard rates, but your ad must be "in-hand." In other words, your ad needs to be ready to go. Sometimes, the ad department will know a day in advance that a space is open and can call you for confirmation that you want the ad to run. In other cases, they may not know until the day of publication.

Most advertising departments can assist you in creating your ad in advance. You then need to let them know how often you would like the ad to run; for example, once a month, twice a month, or four times a month. There's never a guarantee that the ad will run -- an opening must be available.

Work closely with your advertising rep.

Advertising reps rarely inform their clients of remnant advertising space. After all, they want to get top dollar for the ads they run. Ask your advertising rep to explain remnant ad opportunities and discounts and find out what the production crew needs in order to place your ad. The more cooperative you are, the greater your chance of maximizing remnant ad opportunities.

Tip: If you don't want to handle this yourself, you can hire a service to manage your remnant ad campaign for you. One service called MSS-Standby works closely with daily newspapers across the country.

Remember that existing clients usually get preferential treatment when remnant ad opportunities open up. In other words, you have a much better chance of scoring some bargain advertising if you already have an account with the newspaper, magazine, or radio or TV station.