Hmm. I am confused.

ops:
I am in the process of buying a Bovis Home and paid a reduced (special offer) reservation fee of ?99.
Is this taken off the balance I owe Bovis for my house when I complete? The Sales Manager dismissively said "Oh of course!". But I am now having doubts as none of my documentation says anything about the reservation fee being taken into account for the balance owed.
I wont exactly lose sleep if it isn't but tbh if I had paid the full normal ?500 reservation fee then I would be seriously p*ssed off.
Any ideas?