Without going into dark UX patterns, I'd recommend many of the techniques from http://www.goodui.org/
Some specific examples would be to recommend a specific product instead of treating everything equally (#7), use the anchoring effect on prices or trim the cents (#41, #51), or sell in limited quantities (#36).
Another thing to consider would be the the perception your website or storefront has on the prices your customers expect. The concept of horror vacui is why low end retailers (like a dollar store) tend to have very cluttered websites or stores with no space left empty while higher end retailers (like Apple) tend to have more minimal pages or storefronts with ample empty space.
You'll have to decide if you want to create a user experience that leads customers to expect low prices so they know what they are getting, or one that leads to expectations of higher prices (and higher quality) so they are surprised by the prices (and hopefully not disappointed by the quality).