We have had this rescue dog for over one year. He has run of the house and access to the back yard, which is fenced in, through his doggie door. We have 4 other dogs who he gets along fine with. He has been very sneaky and with every chance he gets he pees and poops upstairs. It is very hard to make him go outside to do his duty. We have to physically carry him out and since he is 35 pounds, it is hard. Although he loves his walks out front and will potty there, he seems like he is just too lazy to come downstairs to go out. He has a window seat upstairs where he loves to look out. We have tried keeping him out of the room but he will just sneak to find another place to go. The vet said his health is fine, no physical issues. I have tried the rewards when he goes out but that doesn't work. I never can catch him going no matter how hard I watch him. He is very sneaky. Any advise?

I know this may sound inconvenient but would it be possible to install a baby gate at the bottom of your stairs to stop him going up there at all?

That way you can re-train him without him being 'tempted' at all to sneak upstairs to poop.

Another thought (sorry)

How does he feel about the doggy door?

I know mine don't like using them, they only will if they really have to.

That sounds like a great idea of what Shazamataz just suggested. I would try doing that first unless it is an inconvenience.

Beagles and most dogs will "mark" their territory be it indoors or out and beagles are outdoor dogs. The answer of the gate is great unless he starts doing his business downstairs. All the people I know that have beagles eventually put them outside where they seem to be a lot happier. They are after all bred to be pack hunting dogs.