My little corgi, Gordon, has recently started having potty accidents in the house. Since I initially potty-trained him, he has always been very good about waiting to go outside, but since we've moved to a new apartment, he's been having accidents in the house.
These accidents have not been happening constantly, maybe once or twice a week, but they aren't at reasonable times (like when I have a seven or eight hour shift at work) but when I am home and have recently taken him out to potty.
Gordon will turn a year old this June. Since I've had him, I've moved a couple of times, and he seems pretty content in the new place, besides the potty issues. This is the first time that we've lived in a place where he is the only pet. (Previously I've had a roommate with another corgi and a pit bull, respectively.)
I'm not sure if this new peeing inside behavior is because he's trying to lay claim to the new apartment, as this is the first time he's been the dominant dog, or if he's just testing me because he's almost a year old. To my further annoyance, he's not peeing on the hardwood floors, but instead, lifting his leg onto things, e.g. a guitar case, a mop....
What are some tips on discouraging this behavior?