Hello A. - I don't have much advice on the rug situation but what I can offer is it is possible to get a dog trainer. It's not the least expensive route, but trust me it pays off in the long run! What you get out of it will turn you, your family and your mother into better animal owners for life, and a brand new dog that everyone will be in awe of! Your life will be so much easier! Trust me, we adopted a dog from the pound around December and she was a complete mess due to us not being good owners, or knowing how to "properly" treat a dog and bring her into a "new pack" - the common reality of humans and 'mans best friend' is that we treat our animals like they are human, with that being sad, our dog developed all kinds of issues, seperation anxiety, started tearing things up, destroying the house, not listening etc. We had to learn to give her boundaries, limit her, and bring her back to being the last one in the "pack". Anyways, she is a completely different dog. Polite, respectful, obedient, she never has accidents.
She also has a kennel that she is in WHENEVER we leave the house, this is where she sleeps or goes when she is bad. The kennel was a big help, it created a sense of safety for her, dogs are naturally den animals and they LOVE this. It needs to be just big enough for the dog to stand up, turn around and lay down. Any bigger then that will allow her to have accidents in the cage. Dogs will not go to the bathroom where they sleep. The kennel should be in a place where your family spends most of its time. Its also a place she can go when she is bad (make sure when she is bad that you move the kennel to a place away from all human viewing this will be very effective as dogs are pack animals and being seperated from the pack (your family) is the ultimate punishment. You can even put it outside in a shady cool area. Remember you can not punish them for OLD accidents, only when it is freshly done, you will only confuse her. Also try to train her to go potty in a certain area, start by taking her on a leash. Keep her confined. This is not cruel, this is RETRAINING! In time she will get more freedom when she EARNS IT. You need to strip her away from all freedom. Being out of the kennel is one of them! Our dog was put in the kennel for the majority of the time for nearly a month - 2 months before she earned more freedom, but she had a really bad leader of the pack issue!
The trainer helped immensely! Although we paid a pretty penny, it was worth it. She taught us everything, reassured us and gave us peace. There is no such thing as a bad dog, if the dog has an accident its only a reflection of the owner. Teach your mom and your family to be better dog owners (though I know its not even not your dog!) and you will see HUGE results! Get some books on dog training or house breaking dogs if you dont want to get a trainer. Get the dog on a schedule. Take her out during certain times, feed her only what she needs morning and night (I recommend Timberwolf but that too is pricy and they have other alternatives) the better the food the less bowel movements they have and they dont stink or have smelly farts! Its amazing! A dog should NEVER be left unattended or wandering around on its own. They should always be on a command,.. That may sound harsh, but it takes dogs back to their roots, the real pack mentality. Talk to you Mom about this and tell her if shes going to keep the dog in the house then she needs to give it boundaries and that all of you are going to learn how to be better dog owners, now that there is a dog in the house. If she does not want to do this then you are going to have to ask her to give the dog away. Chances are if you do it with her she will be receptive. You will all learn a lot and benefit from it.
I have a GREAT trainer named Karen with Northwest K-9 Academy ###-###-#### HIGHLY recomended changed our lives! She would have books she could recomend as well. The best way to fix this problem is going to be by preventing it! You CAN teach an old dog new tricks!
Also one more addition - if you can please go to a locally owned pet store. The larger pet chains like PETCO and PETSMART do not carry the "GOOD STUFF" and specialty foods and such. Plus its always good to support the local businesses whenever we can!