I don't know about Pennsylvania, but in California it's ILLEGAL to procede with work on a car without authorization (and has been for decades!!). I give my mechanic a letter (drop it off "early bird") telling him what it's in for... and tell him to CALL ME if you find anything else. They typically make me sign an acknowledgement as to the repairs that have been authorized.
You might check with your local / state authorities (the ones who would oversee automotive repair facilities) as to what your remedies are.
1989 300 E
1992 190-E 2.3