This sets the property to invisible. Remember though, to make it visible, you have to do that back through code..
(defun MAKE_INVISIBLE()
(vl-load-com)
(setq ENT (car (entsel)))
(setq VLENT (vlax-ename->vla-object ENT))
(vla-put-visible VLENT :vlax-false)
)
"Everybody is ignorant, only on different subjects." — Will Rogers