Q: I am about to start a beauty website; how much products should I put on the website… 5k, 10k, 15k, 20k, or more?
A: I think you are asking the wrong question.
You should be more focused on how you can make the site into a unique resource that people will want to visit.
The world doesn’t need or want another giant directory of products without any value added to it.
There must be a compelling reason for people to visit your site.
Don’t worry about how many products will be featured, but rather why people would want to go to the site.
Then scale up the site with your unique content, whether it be consumer reviews or what have you.
Can you imagine going to a site that is offering consumer reviews and just a fraction of the products have any review at all?
I wouldn’t want to return when I can go to more active and established sites, unless there was some other unique value to the site that I wasn’t getting elsewhere.