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Namecheap as the name suggests is one of the cheapest domain registrar at just $10.69 per year for a .com.
Specs
Pros
Pro Supports credit cards, PayPal and adding funds to your account separately
When it comes to paying for domains, Namecheap supports all common payment methods. For most people this will be credit cards and Paypal, but Namecheap also has an option to add funds to your account separately.
Pro Great support with 24 hour live chat
Namecheap support is available 24 hours a day, every day of the year. Their support is provided over live text chat, which has a lower barrier to entry, faster connection, and allows you to communicate easier than other the phone.
Because most of the support you need for domains require you to provide text configuration data, live online messaging is the most efficient way to get fast support. It also does not require your constant attention so you don't have to waste time while the operator is researching an answer for you.