The aim of the study was scientific consideration of an alternative of using mechanization services by farms in comparison to the purchase of new or used technical equipment on the example of grains combine harvesters. Two typological groups of grain combine harvesters were created. In selected groups following makes and models responded to an average combine harvester: A – Bizon Z056; B – John Deere 1450 CWS. Border points balancing the price of service in working hours and surface designed to harvest were established. Investigations showed, that the purchase of a new combine harvester will be rational only in these farms, where minimum acreage of grains and technologically similar plants will achieve: group A – 128 ha; group B – 173 ha. If these services are unavailable, farms can afford purchase of the used equipment for an average price which does not exceed: PLN 89,530 for group A and PLN 17,6315 for group B.