Charging $200 front door installation!!!! Come On!!
lot's of ways you can screw up a door install. lots of skill but looks easy when it isn't.
Piffin may well be correct. Especially if it's a heavy wooden door. A door pro can make these look easy to put in--but DON'T BE FOOLED. There is definitely an art to it; usually not a DIY task.
I also agree that the job should go to a door pro, not a handyman or jack-of-all trades. (Although I'm sure SOME of those guys might do enough doors to know how to do it right.)
Personally (NO I'm NOT A DOOR INSTALLER ) I have struggled with some storm door installs; they came out pretty good--but even these can be surprisingly frustrating & time consuming.
If it's a pre-hung steel door maybe you can get off cheaper, but for a heavy oak door or something like that, call in a pro!