It all depends on what purpose your site will be used for. If you have a business and you have a non-profit organization, I would recommend .org, which you can get by contacting https://www.namecheap.com/domains/registration/gtld/org/. I have my own online psychology school and that's the domain I chose for that. Right now I pay $8.98 a year for a domain name, but the price can vary depending on how long the domain is registered.