Well, so much for that idea. I guess the only effective way to promote an external website now is to plaster it all over social media.
That along with a lot of SEO (Search Engine Optimization) and a healthy budget for a Google AdWords campaigns.
Of course the easiest way to start promoting your website is to utilize the big customer list that you have collected over the years on eBay.
"Of course the easiest way to start promoting your website is to utilize the big customer list that you have collected over the years on eBay."
BINGO.
I never spent one penny on Google or any other search engine. It only took a few years to build my website to the point sales exceeded my eBay store (and similar sites) sales.
Once an eBay buyer has purchased from you, there is no policy infraction in directing that buyer to your website for future purchases.
There is no infraction in sending an invoice with every eBay purchase clearly giving your website URL and email address.
There is no infraction in affixing a label to every envelope or parcel thanking your customers for their patronage and inviting them to visit your website.
Anyone serious about building a long term business should not rely exclusively on one venue (eBay) but expand to other venues or create and manage their own website. The costs of setting up and managing a website is minimal (a small fraction of what eBay charges).
Now, those who sell on eBay as a hobby need not worry about having their own website. Keep having fun and enjoying that hobby.
I retired years ago and no longer sell from my website.
No change have been made in years
Yes I am still using the same host because I have been using the same email address - linked to my website URL - for twenty years and decided not to bother changing it.
As far as paying, that is an assumption you are making. The service is owned and managed by my son-in-law! 
I get a "family discount"!
PS - I should add that the site also hosts thousands of images still being used from time to time.
@73rhc wrote:
"As far as paying, that is an assumption you are making. The service is owned and managed by my son-in-law! I get a "family discount"!"
So you give this great business advice that it's easy and cheap but you keep this little tidbit out! Kinda discredits what you say, wouldn't you think?
Actually, I disagree with your conclusions. Pierre says his site is more or less in abeyance, but is years old. You're judging by the wrong example. Times and technologies have changed vastly where web hosting and website building is concerned, and that makes an enormous difference in an individual's ability to set up a relatively low-cost but efficient selling site.
Even if you don't like the idea of a totally DIY site, the services to set up a private commercial website are becoming so sophisticated that you really don't need to spend thousands of dollars anymore to get a professional-looking, efficient and safe site for selling.
Most web hosting sites now offer à la carte services that permit you to do the designing yourself, using various streamlined set-up tools and templates. You can then perfect the site with add-ons as you wish, or have an expert tweak and tidy for you for a flat fee.
I think all of that can easily be done these days for well under $1,000, often under $500 if you're not after all the bells and whistles. That's a small investment for a commercial start-up online, and let's not forget it's tax-deductible. 
And many hosting services, as you point out, offer online photo hosting so you can build an image catalogue. Those storage capabilities are getting really huge these days compared to what they once were. Things are far different in the area of website creation than they were even 5 years ago.
"Ton of free sites out there doing just that!"
Sellers are free to select whatever hosting service they wish. Some will want a "free" service while others prefer a service where a monthly or annual fee is required.
There is no right or wrong answer. It depends to an individual's needs.
Different strokes for different folks.
"...and these are used successfully by legions of merchants. "
That is correct.
It is also important to note that different sellers in different industries have different needs from a website. When I look at what other stamp dealers offer, most of them supply long list of stamps currently available from stock. Some may be available in multiple quantities while most are "one-of-a-kind" (due to centering and/or cancellation for used stamps).
The site has to meet buyer's expectations. What are buyers looking for? In my business, the average buyer is 65 year old. That is a reality I understand. "Flashy" website is not what they want.
In the "good old days" (prior to my retirement), my buyers were looking for lists - per country or subject - listing availability and prices. From those lists, they would send their orders by mail or email. My site had hundreds of such lists - over 10,000 items overall - to help buyers (collectors) make their selection. A typical purchase would cover ten to twenty individual stamps or sets. It worked for me and my customers.
Of course, I would have a different website if I were selling one item at the time to buyers.
I have learned over the years not to judge a book by its cover.
