My prices are x3 and x4
and I have sales. It all depends on what you are selling, how qualitative are those products and what is the price you think you buyers will take as affordable and acceptable. For example if the product cost 30$ and you sell it for 90$ I don't think is a good idea. But if it cost you 10 and you sell it for 30 and you are confident that it worth this price and competition sell for much more - then you can sell it with this markup.
Think about value you add on every product. You need to add more photos, more copywriting, more guarantees and so on.