Their starting prices are on their website. With the extras I got plus tax and service charge it came to $224 per person.
the price list i have lists $135pp
Also, I believe that if you want BM is a place you can bring your own caterer. I think there was someone on this site or the knot who is doing that and got the pp w/ alcohol significantly down. Sorry -- don't know who it is, but if you are interested you could try posting on both sites and see if anybody replies...
I'm a Bourne Mansion bride to be and I know from experience that you can't bring in your own caterer. The whole place is run by Lessing's and that is who you book with, so they wouldn't let you bring in your own. I was going to try to hire my own chocolate fountain to keep the price down, but they wouldn't let me. They said I have to use their services, which I'm happy to do since Lessings is so well known and has such a great rep. ALso, there prices are different from May to Oct and from Nov to APril. They're much cheaper during the winter months.
