If it's for yourself, and if you spend only $500/yr, then Dynadot gives you $8.75 .com prices. If you spend at least $5000/yr then Dynadot gives you $8.50 .com prices and free privacy. You can prepay the $500 and start using the $8.75 pricing immediately. There is no fee charged to top-up or pay via PayPal.
I think your best other alternative to Dynadot, would be NameSilo. They are really a domainers registrar with lots of free goodies such as privacy. Their discount pricing for 0-99 domains in your account is $8.89, 100-499 $8.79, 500+ $8.69. See the pricing on their website. They have a good, understandable control panel also.
Both of these are free. GoDaddy's Domain Discount Club gives you $8.49 .com prices for an annual fee of $120 (just gone up), but coupons could reduce this by about 35%. They are not domainer friendly, imho. But they do have a great control panel, and most buyers want their domains to be at GoDaddy. So an easy push. There are usually also a lot of cheap coupons for new registrations.