I wrote you a really long reply but then there was a technical hitch and it wiped my message
I was basically saying congratulations and a boardie on here got married not too long ago at the seastar inn near the cliffs in negril her name was tawnee think she is on here if you want to ask her any questions-the set up was lovely and rob who runs this board broadcast the event live for all of us to watch and her family and friends back home.
The owners there are certainly not rip offs and they are lovely people.Call them see what the going rate is perhaps?They did this particular wedding on site but maybe they offer off site services I do not know but they are definately worth a call.

As for 90 dollars extra per person when you are filling up probably 20 rooms with 40 people I think that is quite unfair.Are they offering you no perks at all?
I personally would not book that when I had already brought 40 paying guests to pay for food .I would take them elsewhere.

Jamaica is a lovely place for weddings,call a few different people and places though to compare packages and quotes.I would not pay almost 4000 dollars to a place I just booked and filled 20 rooms for .Ask around.

Here is the wedding section of this website which is very useful
http://negril.com/list.php?item=WEDD