"Kaufen": To obtain or acquire. This emphasised the mutual transaction of cash from a commodity in unambiguous conditions (Alright, it may be used metaphorically too in a similar vogue to English: "Das kauf' ich Dir nicht ab" = "I don't buy [=imagine] that"). Be sure to also watch out for https://donovandimps.wikipresses.com/4348304/how_holz_can_save_you_time_stress_and_money