We've used the cheap little seats that you set on top of the potty that you an get almost anywhere (Target, Walmart, Toys R Us, etc) for around $12-$14. They have characters on them, and come with a pee pee guard which is a must. I like the one that goes on the big toilet because then when you are out in public they aren't afraid to sit on the big potty. If they are training on a little potty, then they may not want to sit on a big potty when you are out somewhere. I bought a little step stool from Ikea for my sons to use to get up to the big potty. These seats are super easy to clean. The pee pee guard stays on well, some seats I have used from Fisher Price the guard comes off every time my boy goes to sit down. Then, I have pee everywhere. Good luck!