When it comes to brick and mortar stores, every business owner, prospective or otherwise, has a lot of expenses to consider. For the store itself, you can take rental costs -- if you're not buying outright -- and the utilities. Factor in any renovations needed, plus there's also stuff like property and fire insurance, applicable health permits, local government permits and the corresponding taxes, etc.
Then there are also the physical assets used in the business: aside from raw materials, there are the tools and any machinery used in production, which also come with their eventual depreciation. Adding employees means allotting money for compensation and benefits, plus health insurance and any government-mandated pension plans, which are also included in the cost of running the business (overhead). That's a lot of slices in the budget pie.
In an online business, you can bypass a majority of these bills. Because it's a virtual
enterprise, you can run one out of your basement, your garage, even
your living room or a closet. You'll need reliable equipment, but most everything
else can be outsourced like data storage, website design, virtual assistance and
even administration. There's no real need to buy the latest thing only to see it
depreciate in value after only so much time.
In running an e-business, things get really different because of its very nature. The first and most basic requirement is a computer and a reliable (and fast) internet connection. Anything you want to do, whatever it is you want to build, is based on having these things -- whether you're
selling something (being a merchant and an e-store proprietor),
having someone else sell something for you (affiliate management),
establish a presence or a brand (blogging and social media), again, your most basic tools are a reliable computer--with good backup, don't forget -- and a steady internet connection.