I'm confujsed about copyrites on stock images can anyone help clarify something?

ok i found a website fotosearch and it says that the images are royalty free and whatnot but when i clicked on the one i wanted to download they wanted to charge me between like i think it was 50 and 750 dollars to download the image.... however i could still save it if i had wanted to i'm uming that the difference is the resolution and the fact that the watermark is gone from the image if you pay for it, but my question is will it be illegal for me to save the Image and use it as long as i am not getting any monetary gain... it's a picture of a wolf, and i'm making a collage of the things i love ie friends, family, wolves, and other things to be determined later lol so all rambling aside would it be illegal for me to use this Image