Yep, they ol' "Hunt for the part problem".
Family already knows the signs when they need to stop moving so that I can my parts, if part is not found it is vacuum cleaner time.
Put a piece of cloth betwen the Pipes and get going, the cloth acts as a trap and will catch the little missing dastards.
NEW place will be flooring all the way and modelling desk moves into a triangular shaped corner(PC) desk which should cut down on the lost pieces, below the chair will be a clear plastic mat to catch runaway parts.