Just curious, just started using this site and I see many have prices, while others don't
Two types of accounts exist. Pro and non-pro. People with pro accounts charge and people without pro accounts do not. Or should not, there are stealth pros too but they're breaking the rules.
Basically what @JasonCuddles said. Additionally if you see someone who says they are charging but they do not have the following pink button on their profile, you need to report them, which you can do by clicking on the [...] button and selecting “untagged pro” as the reason in your report. People who want to go pro must complete an application which can be found by scrolling to the bottom of the site (on the main page if you’re on mobile).
There are two types of account but three categories of user on this site: professional (who charges), client (who pays) and enthusiast (neither). Some people fall into more than one category.
Clients and enthusiasts have identical accounts. Professional and client/enthusiast accounts are similar, but easily distinguishable by the pink Pro or P or Professional, depending on context.
For brevity and simplicity, clients are often considered to be a species of enthusiast.
If someone is charging and they are not a pro, please report them. Thanks. Moderators will take it from there.