Which Canon DSLR to buy?

If you choose the Canon T4i with the 18-135mm f3.5-5.6 IS STM zoom lens you'll have auto focus during video.

Its usually safe to buy a Factory Refurbished camera since it will come with a warranty. When a camera has been refurbished all that means is it was returned under warranty with a defect sufficient to cause the manufacturer to swap it for a new camera. The manufacturer then corrects the defect and sells the refurbished one at a lower price.

If you don't plan on taking a lot of videos, get whichever is cheaper. The reason why the T3i didn't receive gold is because it came out a year later lacking much improvements. Same for the T4i.

The T3i technically has better noise performance than the T4i, you wouldn't notice until ISO 6400-12800.

Refurbished is a broad term meaning that it was returned for no particular reason and reprocessed. If you want to save money, it's usually a good idea to buy refurbished and if the one you receive is, for some reason, in bad condition, just return it for another one.

I'd like to add the option of the 60D. Out of the two, I'd get the T4i, but with the 18-135mm STM lens, which is basically made specifically for the T4i. T4i has a touchscreen and overall upgraded features and build quality, but you may want to look into the 60D as well. 60D is more popular as an upgrade from a Rebel, but the T4i has better video. You can find all three of these cameras for about $50 dollars more/less than each other. Unless you have a very strict budget, the T4i is a no brainer (or 60D)

T4i is certainly the better camera but if price is a problem get the t3i

Q2- refurbished means the cameras that have been previously returned to a manufacturer or vendor for various reasons and the faults are fixed some people say its better to buy the refurbished models since the company finds all the faults and fixes them