.. Getting a coin

One place would be the recycle machine in the corner shop.

If you insert a can into the machine you should get a coin.

Salty is drinking a salt-water drink in a can. When you serve him a boiled egg he will finish the drink and give you the can.

Put the can into the chute in the recycling machine and you get a receipt. Give the receipt to Lenny and you have a coin!