Humm,,, I use a 4" Drop and a Draw Tight "Ball mount" bike rack,, Blue Ox custom modified the drop by welding a "Tong" on it (Ball mount bracket) where the bike rack bolts on.
No problem stowing the tow bar (Blue Ox)
Adding extensions reduces the hitch rating, the more extension (or the more drop) the more the reduction.. Using that 4" drop and a 4,000 towed I pulled the 5,000 pound rated hitch right off my motor home.. A very good weld shop put it back,, and I suspect the part that broke is now rated at aroudn 15,000 pounds (But the total hitch rating is still 5K)
Home is where I park it!