Although I tend to talk quite a bit about getting your startup done yourself, not all businesses can thrive that way. A good home-based startup with lots of traffic and revenue will require quite a bit of customer support efforts, and eventually you will need help to keep it running.
The idea is not to do it all alone, but to grow large enough that you need help. At that point you may investigate hiring or contracting with a support person who can work from home, or contract with a designer or developer and take your site to the next step. Eventually you may need office space and, an accounting person or two, and in-house support.
To make sure you're ready when the time comes, I would suggest investing some share of your profits into low-risk or moderate-risk investments (see your local financial planner), and some share back into your business to improve it and drive more business.
This scenario is the possible future for all solo startups, as long as you have a good business plan and good execution. Don't worry about how you're going to pay for all the office space and employees right now. When time comes your business will be able to fund it.
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