I did not know that different centers used different DR location screens. I am not aware of "Inside Front Door" etc. if I use FD that means at the Front Door, not inside the front door.
I will use Porch which puts location as POR if I am leaving it inside an inclosed porch area. We have a lot of these up north, "arctic entry" an unlocked enclosed unheated (but insulated and warmer than outdoors) area before the actual front door where the doorbell is.
On the second screen of DR locations we have Patio, Shed (several Snap-On dealers have us DR to their shed), and Carport.
I will go into someone's house if requested when I feel it's appropriate, i.e. elderly cnee and heavy package but only far enough to get it in to where they can close the door and still get by it. I always tell these people that I'm actually bending the rules to do this so they are not surprised if another driver does not feel comfortable doing the same thing. As Fragile said it doesn't make sense to deliver a heavy package to someone and put it where they can't physically get at it or move it.
OTOH I agree totally with Upstate if customer is such a butt that it ticks me off then I am going to give you minimum service. Outside UPS I am an umpire so it takes a lot to actually tick me off. But I don't recommend doing it lol.
As far as customer trying to accuse me of theft after I stepped in their house they could do that just because I was on their property. Someone needs much more evidence than my mere presence to go after me for theft, evidence that does not exist. So I really am not worried about that.