The vaccine has been proven effective for people under 26. Don't let money be the reason you don't get it. Pay for it out of your own pocket. Sure you may already have it but maybe you won't get a high risk strain that the vaccine provides coverage for and get penile or anal cancer from this disease?
One gotcha: There is no booster shot for the vaccine. It hasn't been around long enough. No one knows what will occur after 10-20 years but by then, its possible drug companies will have booster shots available. No vaccine is forever.