It's a long story, but my grandmothers managed to wee on the rug in the bedroom, would a steam cleaner sanitize & get rid of the smell? I also wanna get clean the rug & upholstery in the living room which has gone a bit grey when it should be cream.should I get a steam cleaner? Or what else can you suggest?

I would hire a professional carpet/upholstery cleaner if I were you, if you want it done right. I haven't had much luck using steam cleaners, myself. I don't have much faith in them.