I've always made a simple 'tripod' type stand from a bent wire coat hanger and paperclips as tiny 90° 'hooks.' Easily adaptable to pretty much any size or configuration of model, allows 360° access for both building and painting, without having to touch or hold the model itself. (But simple to remove if needed.)
For a/c models they go on the stand once basic wing-to-fuselage assembly & cleanup is done -- and usually don't have to be removed until the model is finished, unless something like tricky landing gear alignment is required on a flat surface.
Cheap, versatile, and prevents pretty much any accidental wear and tear to the model! 