How permanent is laser?

I am considering this treatment to reduce hair on chest abdomen and back as part of a sexual reassingment. There are several things that concern me,

One: Will the treatment be afected by the hormone treatment I am receiving?

Two: How long is the recovery time froma treatment? I am fair skinned and my hair is medium brown.

Three: Will this be permanent?

Four: Is there a possibility of a scar from the laser? I am not asking for a percentage like a Casino odds maker. I am asking like has anyone ever been scarred. Frankly if that is even a remote possibility I need to know.