I'm looking in to getting one but I want to know what the advantages are?

You can do 10 more quests each day, play random every 1.5 hours, get 5 more pets making a total of 10, wear another layer on each piece of clothing, ect.

All the perks are listed on THIS PAGE. I personally couldn't survive without my autopricer. :)

top right corner of any page under your username and links to your vaults and stuff there's a link to the cash shop. if you click the gold account tab its all listed there.