$900 is a little high but look at what comes with the kit! The gear for the Ziroli Ercoupe is $125 so you could start adding there. This one is larger too.

BALSA, BASS AND PLY CONSTRUCTION. BALSA USA'S "FALL-OUT" DIE CUTTING. PLUG-IN WING PANELS W/ALUMINUM TUBES. SCALE OUTLINE. SCALE RIB PLACEMENT. SCALE SLIDING SIDE WINDOWS. FORMED WINDSHIELD. SCALE CAST ALUMINUM LANDING GEAR/FUNCTIONAL OLEO STRUTS. SCALE STEERABLE CAST ALUMINUM NOSE GEAR/FUNCTIONAL OLEO STRUT AND SCISSOR LINK. FIBERGLASS COWL. FULL SIZE ROLLED PLANS (7 SHEET). PHOTO ILLUSTRATED INSTRUCTION MANUAL. COCKPIT INTERIOR KIT (including: cargo compartment, interior sides and floor, seat, instrument panel & gauges, scale control yolks, even scale glove boxes! COMPLETE NAME BRAND HARDWARE PACKAGE (Including: wheels, fuel tank, carbon-fiber contol rods & fittings, pinked tape for rib stitching, scale rubber weather stripping, scale rivets for the side windows, all nuts, bolts, screws, control horns, and more!) NUMEROUS SCALE FEATURES (Including, scale inspection rings, aluminum landing gear strut covers, aluminum wing strips, scale wing walks, clear landing light cover & etc.) SCALE DECAL SET (Includes: Ercoupe badges, scale nomenclature, no-step, no-push, fuel tank capacities and octane rating, even the instrument panel placards as required by the FAA.)