If you're interested in the correct answer, the laptop is classified under Customs Tariff item No. 9993.00.00. Customs Memorandum D8-1-1 discusses in detail the conditions under which goods may qualify for duty-free entry under that tariff item and identifies those circumstances where temporarily imported goods are entitled to GST relief.

Take a read if you like (it's 31 pages):

http://www.cbsa-asfc.gc.ca/publicati...d8-1-1-eng.pdf

I'd still recommend what I said in my earlier post.