Sorry, forgot to answer the Wattage question.
Typically yes (although I found my stove was labelled incorrectly -- very rare and odd). I'm not sure what an inspector will officially ask for, but for standard appliances that use plugs (i.e. that can be changed), the maximum of the appliance rating or 80% of the circuit rating might be more appropriate. For hard-wired appliances (like A/C, hot water tanks), you can certainly use the rating of the unit as they cannot be "swapped" by the customer without due consideration. [I'm stretching a bit here in this paragraph as I don't know for sure.]
Most appliances will give a maximum current rating (e.g. 12 A) and an operating voltage (220-240V). Sometimes, there will be a peak current rating (typically for compressor startup) and a continuous load rating. For load calculations, you can probably get away with the continuous current rating (although the circuit wiring and breaker must be rated for the peak current).
You always need to use 240V for the load calculation (it says so in the code, section 8-100).
If you cannot find the rating of the appliance, then use the breaker rating (which will be slightly higher than most appliances), or if you want to, use 80% of the breaker rating, as that is officially the maximum load you are supposed to have on the circuit.
A reminder, I'm not a certified electrician or an expert -- just done lots of reading recently on this. And the inspector's interpretation of the code may vary (and their's is the only one that matters in the end).
Thank you so much once again!