We have successfully put multiple clients on page 1 of Google (as well as Yahoo & MSN) for generic phrases. Time/cost depends very heavily on the amount of competition, the keywords you are targeting, the amount of time you or an employee can invest to work with us, etc.
Your website doesn't have to cost a fortune - we did a complete, from scratch solution that a printing company in GA uses to do their order processing, invoicing, stock level management, customer database, label printing, etc. for less than 4k.
The best approach for a specialized ecommerce site is to use an open source shopping cart solution like Magento or Zen Cart and heavily customize it. That way the foundation is already laid, and the programming & design cost is cut considerably.
With that said, you will get a wide range of advice and price ranges. In most cases - especially with Internet marketing - you get what you pay for. People who work dirt cheap have to take on so many projects just to make ends meet that they can never really focus lon anything and excel at it. I feel our prices are about mid-range but our work is top quality.
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Google isn't as dumb as you think.