Let me clarify. Based on my experience so far it is 21% off RRP, because asked the pricing of 6-7 models and compared the quotes to the RRP. Prcoedure is this - I give the PNS camera I am trading in to Canon, and choose the model i want from the list of available models (it can be a PNS model or a xxxD model). They will quote a price.
So if RRP for the model is say $100, the price quoted will be around $79.
I have never used a DSLR for the trade in, only PNs so far. Model is A70. Confirmed verbally with the staff at CSC that any Canon PNS model in any condiiton is acceptable.
A70 is way back in time where PNS is up to 3.1mp. Hope this helps.