Adding Internet marketing to your advertising budget isn't easy, because you'll most likely have to take away some money from another part of your marketing to devote to the Internet.

Web designer and planner, Bill Koelzer and co-author of Internet Marketing in Real Estate, Prentice-Hall, runs into this problem all the time with agents. He advises the following:

First, list this year's main ad budget categories. These might include: Newspaper ads, door hangers, direct mail to farm lists, business cards, letterhead, brochures, signs, flyers, photos, etc. Each category should have sub-heads, so under "Newspaper," you might have Los Angeles Times, The Register, Home Town Newspaper, etc., then under those you might have Business Card-sized ad; listing ads, classified ads, etc. Some costs can serve more than one purpose, if your newspaper also offers online classified advertising for example. Agents who buy ads in some homes magazines can also get or negotiate to have their homes and personal ads featured online.

Alongside each subhead you make two columns. In the first one, you write the dollar total of what you spent this year. In the second column you write what you think you ought to spend next year. When you are done, you have a basis for planning your promotional budget for the year - except for "Internet marketing."

You arrive at your Internet ad budget by first factoring in the "essentials" that you need in order to avoid losing market share to the growing number of Realtors® getting into web marketing.

The most effective listing service sites are the full priced deluxe editions with lead generation features, so budget for at least two to three of those. Weigh the sites that deliver the most traffic and have the most affordable tools, including email or pager notifications when you get a lead. Weigh how many of these tools you can get for the price, and then follow up by tracking the solid inquiries and closings you get for each category.

A custom site could run a minimum of $1000, with an additional $500 for changes you'll want your web site designer to make during the year. Be sure to include monthly charges from an ISP for hosting the site at about $40/month or $480/year.

What you want to spend is up to you, but some agents on the Internet spend as much as 25 percent to 75 percent of their marketing budget on the Internet, but that is a number that should relate proportionately to how much effort you plan to put toward working the Net. The higher the amount you spend the more prepared you need to be to cross-promote, develop niches, work the search engines on behalf of your sites or pay someone to do so, and to track your results. And most important of all - answer your emails.

The best sites will give you traffic reports so that you can track your leads and compare them to the results you get from your other Internet marketing as well as your off site leads. These should include breakdowns of which partner Web sites deliver what percentage of your leads. If you are not sure where an Internet lead came from, you can make a note to ask your buyer before closing.

Some sites may deliver leads indirectly. You may get a referral from another agent for example, based on your positioning on a Web site, or a directory. Referrals from friends, relatives and closed transactions can be as much as 37 percent of your business according to the N.A.R., but referrals from other agents who are relocating clients across the country, or who are licensed in several bordering states, should not be overlooked. Ask for referrals from agents on your Web site and be sure to publish your policy for paying referral fees.

Some Internet tools will be more successful later than sooner as consumers also find out about these sources. Early positioning may be key. An example of this is the Agent Locator directory on Realty Times in which positioning is offered on a first-come-first-serve basis, rather than alphabetically. Renewals allow the agents to retain or improve their positions.

Keep in mind not only how much Web sites cost, and how many leads, but other lead generation tools such as online newsletters and local banner ads in your online city, local chamber of commerce, or visitor guide. You can find out where these are by going to the search engines and keying in your city.