I sell some livestock on craigslist and I will say that people will ask you to send more pictures at any hour... even if they have little intrest in buying, or lack the ability (no trailer, no accommodations for the animals). I've learned to take on a no nonsense approach toward online customers.
Just last night a guy asked me to hold 8 chickens for him for a month while he builds a chicken coop. I did him the favor of asking for a deposit and he acted like I was trying to rip him off.
I have learned these people respond well to simple commands, stated firmly. I was in the car business for years.. and while it's true car salesmen lie, They don't lie a 10th as much as a customer does.
Once an old guy told me: "if they ain't living they ain't buying, and if you ain't lying you ain't trying."
All that being said.. Screw this guy. He may have a pipe for sale, but it sounds like he wants you to kiss his ass for the opportunity to purchase his pipe.