"Custom Cabin" was Waco's own description of the aircraft which despite minor differences, were all fabric-covered biplanes.

Fuselage structure was typical for the period, being welded steel tubing with light wood strips to fair the shape in.

The main landing gear was sprung with oleo struts, and a castoring tailwheel was fitted on all versions except the VN model, which had a nosewheel.

[3] The Custom Cabin series, with its improved performance proved to be popular and many were purchased by small commercial aviation firms and non-aviation businesses.

Many served in the Canadian bush country, where they normally operated on skis in winter and EDO floats in summer.

[4] With the onset of World War II, examples were impressed into the air forces of many Allied nations, including the US (USAAC and US Navy), the United Kingdom, South Africa, Australia and New Zealand.

[5] A single impressed ZGC-7 referred to as the Big Waco, RAF serial AX695, was used by the British Long Range Desert Group (LRDG) along with a Standard Cabin YKC named Little Waco to support their activities behind Axis lines.

The Waco Custom cabin series included all of the enlarged-cabin sesquiplanes from 1935 and can be further divided into six basic models, OC, UC QC, GC, RE and VN, with additional subtypes differing primarily in engine installation (indicated by the first letter of the designation or by a low dash number, i.e. -1, -2) and by model year (dash numbers -6, -7, -8).

The RE series is more refined aerodynamically than earlier models; the wings are fully plywood-skinned, and instead of a bulky compression strut carrying lift loads, a more conventional set of streamlined flying wires completes the wing structure.