Green’s Dictionary of Slang

(US) a mean, contemptible or insignificant person.

1939		W. Winchell On Broadway 24 June [synd. col.] They are nickel-and-dimers [...] Spend little.
1947		Berrey & Van den Bark Amer. Thes. Sl.
1973		J.R. Naish Bloodletters and Badmen 348/1: The dedicated young killer had learned that one of these men had referred to his father as ‘a nickel and dimer’.
1988		R.R. McCammon They Thirst 78: Though he was just a nickel-and-dimer, he was making enough money to keep himself in good threads.
1999		J. Ridley Everybody Smokes in Hell 74: A dreamer, a nickel-and-dimer.
2003		C. Stella Charlie Opera 121: ‘Benny Besognio?’ [p...] ‘Nickel-and-dimer’.
2019		D. Winslow Border [ebook] ‘Fucking cops—nickel-and-dimers’.