This is pretty simple, just do not add a key right away when you hit 20 to your RAF trial account (or any trial account for that matter) and do some quests at 20. Because you can't gain any more experience, you'll gain about 1-2 gold per quest and easily get a quick boost up to 10 gold! This helps the most when you have no previous characters on the realm to send gold from (or if your RAF buddy is just a cheap-o).
Also, I take this to be an exploit because... I said so, grr!