Maximillianos - in this particular case I think they will notice. The asp bit runs site wide and almost any page would clearly be incomplete without it, unfortunately.
Artefaqs - is that remark about transfer of domain from experience? That would be a good approach from my view. Transfer the domain to them as proof and that requires transfer of money to me.
But this whole thing now appears quite complicated. If the domain is they key, what about the hosting, after all that's where the code resides? Is it normal to give the buyer the password to the hosting account and let them keep the account / copy the code to their own account? Sorry to be a pain and keep asking! Anyone had specific experience?
Hopefully the guy will buy my website and I can document my experience along the way for others to benefit from it. Possibly I might get completely conned and still people will benefit from my experience. More likely of course, the sale will still fall through.