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An expert in the field of creating "virtual storefronts" estimates that as many as half of all businesses that have been around for more than 15 years are invisible online. For years, places such as local pizza parlors, auto repair shops and plumbers have survived without Internet identities.

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“There’s no hard data on it since it’s impossible to really count who’s not online,” said Jeff Lerner, founder of Xuril. “But there is a shockingly high number of startups and established small businesses that have not even done the most basic, even free, things to meet customers online.”

Yet the fact that older, established businesses are getting by without a web presence does not mean you should try it -- especially if you’re an entrepreneur starting a new venture. Whether you’ve been in business 20 years or 20 minutes, here are three steps you should take to make the most of your online business opportunities.

1. Get what’s yours.

Believe it or not, many of the basic things you can do to get your business online are free. Or mostly free.

Getting a unique domain name through a service such as GoDaddy is pretty easy and inexpensive -- around $15 (you'll pay more to maintain the website online). Other services, like Wix, offer domain space and basic design services for free. Yes, free. And creating a business Facebook or Twitter account is also free.

Even without a website or homepage for your business, you'll find that some important web-based features are still available for your business. Features like getting your business connected with Google Maps, so customers searching for you can find where you are, are free and often overlooked by business owners.

“It’s unbelievable the free web tools that businesses overlook. And while anyone can do it yourself, there’s some science and a bit of art to doing it well.” Lerner told me. For example, he explained, if two similar businesses register with Google Maps, the business that ends up being listed first will depend on a variety of not-so-obvious factors. “So, it may be worth chatting with someone who can help,” Lerner said.

2. Advertise.

Advertising costs money -- which may knock if off your to-do list for a while. But tossing a few dollars at some search advertising or social media promotions can pay off.

Once you have a free Facebook page for your business, for example, boosting a post (the Facebook equivalent of advertising) can be effective and inexpensive -- like Starbucks-inexpensive. It’s a good way, too, to share breaking news or offer customer incentives, like discounts.

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3. Plan and invest post-click.

If a ton of businesses miss the boat by being absent or invisible online, even more make another avoidable error: failing to plan for what they'll do once potential customers do find their businesses online.

The concept of "post-click" engineering and marketing -- building the experience visitors or future customers will have when they finally do reach you online -- is a serious business opportunity with growth potential. Getting smart about post-click can make a big difference, and work in your favor, even if your business isn’t a digital or web concern. In fact, that may be when post-click actually does you the most good.

Radio, for example, has long been challenged at finding a way to truly capture a digital customer and a market base for its nonweb medium. But Greater Media, a 59-year-old company which runs 21 radio stations and is considered an innovator in the digital space,­ views post-click as a way to engage its target audiences and those stations' advertisers.

“Our web profile was relatively flat before we looked at our post-click options,” said Peter Smyth, chairman and CEO of Greater Media. After bringing in the post-click marketing platform Jebbit, however, things changed, Smyth said. “We saw an immediate jump in our numbers overall and participation with our content and products,­ which helped to increase our bottom line.”

There’s no limit to what a business can spend online. Custom websites, advertising and outreach can break the bank if you let them. But there’s no reason, either, to go that far when a few simple, free tools and some strategic advice and investing can make all the difference.

Making an effort to claim what’s already yours, doing some advertising and taking a hard look at post-click will not just increase your image, it will increase your profit margin, too.

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