It's simple. These are ballpark figures for a simple Central park wedding (or Brooklyn Bridge, etc.) We have heard HORROR STORIES of simple park weddings that are far above these rates. Be watchful. All you really need to do is pay an officiant's fee, and a $25 permit. DON'T PAY MORE!
Park Permit - Apply Online, $25. You can often have this mailed to your officiant's address.
You just go down and pick it up together 24 hours before the wedding. Simple. No-one needs to GO WITH YOU. All you are doing is showing your ID and purchasing the license.
Marriage Officiant - Fee varies, generally $300-400 depending on requirements, time, location. Photographer - Fee varies, depending on amount of time and how pictures are processed and delivered. Shop around! Ask your officiant for a photographer they have worked with.
Flowers: Pick them up at corner florist or go down to Chelsea.
If you go up to the Observation Deck at Rockefeller Center, you will need to pay the admission/elevator fee for your wedding party, and the officiant. The Conservatory Garden and the Brooklyn Bridge Park (parts of it) may be more expensive. But the permit for all others parks is only $25.00
And yes, a tip is always appreciated.