Better be safe than sorry
Own at least 2 of the same model, factory, and HW revision
Own at least 4 brands of calculators
Collector of taste
Own at least 10 different models of calculators
Own at least 10 calculators
Own at least 2 brands of calculators
Twice as many as most people!
Own at least 2 calculators... it's a start!
Own a France-specific calculator (76.fr, 82 Stats.fr, 82+, 83+.fr, 84 Pocket.fr, 82A, 83PCE, French Casios, French brands…)