Hamilton housebroke us pretty quick, but he still has accidents about twice a week (we've had him for 5 weeks - and he's 13 wks old now). The day we brought him home, he didn't go for like five hours and we kept taking him out and putting him on a weewee pad and nothing! I was like "This is amazing! This dog can go so long between pees!" That ended quick. Apparently he was just too busy with checking out new stuff to pee. At first, we took him out every 30 minutes, used "hurry up" as his potty phrase and gave him tons of verbal praise every time he went. We were trying to catch him before he needed to go, since we knew he couldn't ask. We gradually extended time between trips out, and now he can go an hour in between potty trips during the day - though he can go nine hours overnight which is kind of frustrating when he does pee on the floor 10 minutes after he peed outside. We do recognize some signs that he needs to go though - he disengages from whatever he's doing (he's always doing something) and sort of walks away from us, and starts sniffing. Then it's grab him and run out!
We're also teaching him to ring a bell when he needs to go out, which has saved us from poop accidents more than once!! Sometimes we take him out, he pees, and wants to come back in, and 15 or 20 minutes later he's ringing his bell and we're like "Seriously dog?" and take him out and sure enough he's gotta poop! He's not using it reliably for pees (and does use it to manipulate at times), but we do have him "touch" the bell before we go out every time.
Otherwise... the only thing that helps is always having him within arm's reach unless he's JUST gone out - if more than 15 minutes has elapsed since he's gone out he has to be within arm's reach again. We also bought the largest bottle of nature's miracle the store had and uses it liberally when he does have an accident! I'd say now if your pup can go 15 minutes after she just went, if she isn't confined take her out every 15 minutes and praise praise praise every time she goes. If she is going out and not peeing every 15 minutes extend it by 5 minutes at a time until you figure out what her limit is.
