In my personal opinion, a website is not a must have. Yes it has its benefits but also demands more work in terms of promoting the website and not just the products you are selling.
But a website is certainly something to grow towards to.
I would start with simple free adds. While they are spinning and attracting some potential costumers and already creating even minimal traffic, use the time to concentrate on the next step, which are the social networks.
Social networks are always present and you certainly have access to one or more of them. You can create a product page on Facebook, for example, and then when you post a new free add just attach the link to it.
The next step would be a blog. You can create it for free and post all your links and product reviews there and with ads just redirect all the traffic to it.
The last step, with your business developing and growing, would be a website. And by that time you will have a clear concept and idea in your head about what it should look like and how it would benefit you. Just to create a website page to have something and not to think it through is just premature eagerness.
To summarize, think it through, and don't make something just to have it, but make a good plan and stick to it. A Website without a good structure and idea will demand more work with fewer results.
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