The highest floor

The auctioneer's smile seemed to have deepened as he heard this and he clapped his hands enthusiastically as he asked, "I was right, wasn't I? You have been here before!" 

Marvin nodded his head with a smile as he confirmed it.   

"You were the one that bought the..." The auctioneer's eyes narrowed down on Marvin as he tried to remember what the boy had purchased last time.

Marvin chuckled as he shook his head and spoke, "You don't need to remember it. I am a regular. I've bought so many things from here that even I have lost count of them." 

The auctioneer also chuckled as he heard this and nodded his head happily. It certainly felt good for him to hear that there was such a regular customer who was willing to waste money in these auctions. 

"That's right. It's always a pleasure to work with such great customers like you," The auctioneer flattered Marvin with a smile.