Making the common name for this Make-Up Artist official, with one title unconfirmed (UPC 610583343892) as listed below.

CLT, after verification. Current status within parenthesis:

Bob Osterman (12/12):
The Best of The Andy Williams Show (unconfirmed)
Step by Step: Television Favorites (verified by me)
Perfect Strangers: Season 3 (verified by huskersports)

Bob Ostermann (27/32):
The Sting II (verified by me)
Mama's Family season 1 (verified by me)
Full House: The Complete Second Season
Full House: The Complete Third Season
Full House: The Complete Fourth Season
Full House: The Complete Fifth Season
Full House: The Complete Sixth Season
Full House: The Complete Seventh Season
Full House: The Complete Eighth Season (ALL episodes of the series from season 2 to season 8, checked one by one, episode by episode and verified by me)

Robert Osterman (5/15):
Cops and Robbersons (verified by me)
L.A. Story (verified by me)
Perfect Strangers: The Complete First & Second Seasons (only two episodes in total, verified by me)

Robert E. Ostermann (1/19):
Monster House (verified by me)

Robert Ostermann (1/1)
The Sting II (invalid credit, verified by me)


Note that once all profiles have been properly contributed, the CLT results will change quite drastically in favor of the established common name.
Even if all profiles for Robert Osterman would be contributed, there are not enough titles of them to change it around.
However to make the CLT fully accurate, it is (in my opinion) necessary to fill in what is missing.

I aim to contribute as many profiles as I can manage, but any help would be appreciated.
I have currently submitted the few profiles for The Sting II and next on my list is Monster House, and so on.
Once the profiles are approved and released I can revisit this post and update the CLT results.

Quoting T!M:

Quote:
The seven seasons of 'Full House' in which he appears should each be listed seperately, resulting in 9 titles for Bob Ostermann, which would eliminate any ambiguity.

You're totally right.
Thanks for your kind wording. 

As noted, Bob Ostermann is credited in every episode for seasons 2 through 8 (much like most other crew actually, and the credits look even for each season like a copy/paste job).

I guess it mattered that I had had no sleep after all, while pondering over this. I forgot that each season counts as one title, not one profile. Correct?
Titles matter more than profiles and that's the deal breaker here.

Either way, being the perfectionist I am, I still do think we need to contribute all profiles involved so the CLT will show the proper numbers.
I have (to start with) added all profiles to my "to-be-edited collection".

Quoting huskersports:

Quote:
Perfect Strangers: Season 3 - Bob Osterman

Thanks. I had missed adding here that it was in the DB. I had already checked it myself, and I was about to make a contribution for it too.