My BEST piece of advice is save right before you go into the store. Talk to him and if you don't know the answer to the riddle, OR if you don't have the answer in your inventory (which is possible) reload and try again. If he kills you and you "retry" you will have the same riddle. However if you load from before talking to him it will most likely change your riddle. I've seen 5 different ones so I don't know how many there are.
Thanks to TurdBoi for this information as well- "Just to add if you have the haunted camera, take a picture of him and look at it as it will tell you the area the item is from which can make it easier."
Aside from those hints here are the riddles I've gotten and answers OR riddles and answers given in comments. I will no longer be expanding the list. However if people want to keep commenting so that we can have more answers that would be awesome. If you want to comment with your riddles I am sure anyone that still needs help would appreciate it.
Riddles I've seen and know the answer to (I don't remember the exact wording but it should be enough to get it for you)
Answer: Massage Oil
Riddle: Something like- after a stressful day light some candles and rub me on your face
Answer: Blue Rose (I saw this one on a video)
Riddle: Any other color I would still smell sweet
Answer: Old Shoe
Riddle: I don't remember the riddle at all, I just remember that it ends with "would be terrible to live in" and I knew right away
Given by TurdBoi-
Answer: Decorative plate
Riddle: On a wall, not on a table. When you dine, I am too pretty to help.
Answer: Locker Key
Riddle: The key to privacy in a sea of your peers
Answer: Crumpled Paper/Note (from the school)
Riddle: Discarded thoughts, scrapped, hidden, but never forgotten
Given by AnimatuhYT-
Answer: Missing Dog Flyer
Riddle: Bring me a plea for a missing best friend
Answer: Toy Dino
Riddle: The king of reptiles, on a much smaller scale. But with imagination, still turns small soldiers pale.
Answer: Perfume
Riddle: I am an ocean breeze and a flowering field. A warm embrace. A refreshing shower.
Answer: Place Mat
Riddle: Every day, I hold up three squares. What am I?
Answer: (got this twice could never figure out the answer, it's something from the mall)
Riddle: I can build a bridge and go fishing. Win hearts or declare war.
Answer: TV Remote
Riddle: Always hidden when needed, never where I'm left. I crawl under cushions, while you sit unaware.
Given by oneEyEstrang22-
Answer: Cards
Riddle: I can build a bridge and go fishing. Win or declare war.
Given by oneEyEstrang22
Answer: Car Magazine
Riddle There's only one weapon strong enough, brutal enough, to defeat a gross spider
Given by Vingador Brambz
Answer: Pamphlets
Riddle: "Looking for answers? With all due respect, I know all that is known (on one narrow subject"
Given by Vingador Brabmz
Answer: Lipstick
Riddle: I enhance that which I cover up. I entice when I'm left behind"
Given by Vingador Brabmz
Answer: Action Figure
Riddle: Considering I cant speak, i'm an incredibly character