We found that Toto was very particular about her wee wee pad. She is pretty much fully trained but will still sometimes have an "accident" if she is in an unfamiliar place or really stressed! We have learned to watch her closer when we are in these situations. She also will not use her pad if it's dirty!!
We call her "Miss Prissy Paws"!! My routine is pretty much ... put a clean pad down [I also keep a supply of pads cut into 4 equal little squares] ... when she goes pee, I put the little square on the spot and repeat this throughout the day ... if there is poop, I simply pick it up with a piece of toilet paper and flush it! This always gives her a clean pad and cuts down on the cost! She is happy and we are too. One interesting thing we have found, now that she is older, if we have to leave her alone and she has to stay in her X-pen ... even though there is plenty of space for everything she needs, she will not eat/drink, pee or poop until we get back! It's routine ... she happily "greets" us when we return ... zips around the room and rushes back to her pen, pees/poops, gets a quick drink of water and wants to play!!! She will sometimes use a pad a couple of times if I don't notice that it needs to be "refreshed" but she tries to let me know that I am "lax" in my duties!!!