I agree that that you need to work on house breaking your dogs. It's never too late to start. My chihuahua was 6 years old when I adopted him and he wasn't a a bit house broken, but it didn't take long to train him.

If you don't want them to go outside then I'd at least train them to go on pee-pads . When they go in the house clean it with a cleaner such as Natures Miracle which has natural enzymes that completely rid the spot of any oder.