My first daughter was trained at 18 months she is now three and now my 18 month old is asking to go to go potty on her own so hopefully i will be able to declare her fully trained in a week or so.
both of my girls (as well as the three foster kids i trained) didn't stop having accidents till i took the pullups away. they need to feel gross in order to stop having accidents.
i let the kids play around with the potty for a couple of weeks and if they ask to go i take them. just praise like CRAZY if you catch them going on the potty. then we do a week ofno pants so i can see what their bathroom habits are. then after that i put them in big kid underpants and they are trained within a week. hope this helps!