Which is the stock of spare parts recommended for a full operation of 20 hectares per day?  Engines, rotors, landing gears, filters, an arm? Any electronics that may fail? Thank you very much for your help.

Got some information from my DJI dealer:

Pumps x 2:  $105 each
Air filter x 1:  $9.00
Tank filter x1: $25.00
Sprinklers filters (pack x4): $20.00
Nozzle x1: $10.00
Propellers x8 CCW: $180.00
Propellers x8 CW: $180.00
Landing gear Right: $108.00
Landing gear Left: $81.00
Landing gear foot (tube) x2: $42.00
Arm T-connector x1: $45.00
Arm tube kit x1: 69.00
Oval arm x1: $89.00
Motor: $118.00
Battery MG12000-P (NEW): $599-650.00
Battery connector: $20.00

????????????????????