Thats model U4089
circa 1976, and the LAST rear conversion, narrow bag convertible. This was a promo model, and could be bought new at discount stores for $59.95 with a 1031 set of tools.
As to the bidders: Without being too unkind, one is a little troll who sends you hate mail thru ebay if you out bid him. I don't know who the other is, but these two meatsticks have been fighting and bidding prices way WAY up the past couple of weeks. Most every older Hoover Convertible has approached $200 before the auction is over.
The irony is the one is actually in the vacuum business and should be able to find whatever they want, but instead they get into pi**ing contests on ebay and then throw tantrums when they don't win.
I would say that neither one is the sharpest tool in the shed..