It depends on you. Stop and think about how that visitor finds your site. That prospect started as someone with an interest in gathering information about real estate in your area. They spent time and effort to go to the search engines or responded to your email or wanted more information about the property that you advertised. If they find your site interesting and useful and if your Website is designed to motivate them to respond, they will contact you and you've got a prospect. If you do not treat the lead as valuable and let it get "stale" you will find that prospect has contacted someone else when you do finally get to them.
First and most important of all is to have a site that is so well designed and so full of information that once a prospect visits your site they will stay until they reach the point of needing information that they cannot get from the internet.
The site must be "user friendly" with easy navigation and readily available tools for asking for help. Serious ‘turn-offs’ are requiring a visitor to "sign in" or "register" before they've decided if your site has anything of interest to them. It's kind of like having a sales clerk meet you at the door of a department store trying to get your credit card information before you've even looked around.
If the site is well designed then the process of editing pages for maximum position and targeted indexing on search engines is the next step. There are literally millions of competing web pages. All of these are competing for position in order to have a chance to attract a visitor's attention. A great deal of thought should go into the invisible editing of your site's pages.
The prospect will have a choice of dozens of sites regardless of which search engine he or she uses and regardless of what search phrase he or she uses (there are dozens of search engines and thousands of possible search phrases). If your title and description stand out as being well thought out and informative you will get more than your share of the prospect traffic.
There are still a relatively small number of popular search engines—about 5 that account for over 90% of the search engine traffic yet submissions are close to ten times what they were only a couple of years ago and the numbers are still rising. Advertising revenue which was once the mainstay of search engines dried up as the "DotComs" used up their venture capital. The search engines have had to find new sources of revenue. That means that the "free lunch" of search engine registration of sites is over.
Additionally, to increase quality of their indexed sites, most search engines have increased the level of human review of their submissions. As a practical matter, real estate sites looking for search engine traffic must now budget for professional editing of their sites, professional submission of their sites, and payment of fees to the search engines to get their site reviewed. The result is that you can pay plenty for search engine visitors and so you should weigh the cost against the bottom line you can expect.
What is a "Pay per Click" search engine? One of the new business models for search engines is the "pay per click" where you bid for position on popular key phrases. For instance currently on Overture.com you can achieve #1 position for the phrase, "Sacramento real estate" for $3.25 per clickthrough. It is significant that your competition is willing to pay that much for a visitor to their site, and as a practical matter you should consider what others are willing to pay for a visitor as valuable information in your own planning. The strongest point about PPC is that you can, if you keep good records, actually determine the bottom line value of each clickthrough and make your decisions on the cost of schemes that claim to get you a lot of search engine traffic. (If you want to see what others are saying about SEO.
Most of these search engines review submissions so that you must have relevant pages. The submission to these sites is very time consuming if it is done right. (Think of how many relevant search phrases you might want.) Some commercial sites submit 15,000 phrases and more. The approach to take is to estimate what the value of a targeted clickthrough is for you for each engine and budget accordingly.
For instance: Suppose you felt your average sale to a search engine generated prospect would be a $500,000 home and that your sales commission would be a portion of $15000. You then estimate that it takes 5 prospects to result in a sale. Upon investigating you decide that you will get one prospect from 500 visitors to your site.
That means that your search engine "cost of sale" would be the cost of 500x5 clickthroughs or 2500 clickthroughs. At 10 cents per clickthrough your cost per sale would be $250. At $1 per clickthrough the cost would be $2500. In reality some of the engines would produce better, more targeted traffic and might require fewer clickthroughs than others for the same cost. You would have to do the math and make the decisions.
Web site positioning and web site optimization will remain important, but only part of the marketing picture.