I've had good luck with "scat mat" type products - but the beeping ones, not the shocking ones. They're pressure sensitive mats that you can lay out on the couch, and if they try to get on the couch it beeps at them. No shocks, just sound. (They do make shocking ones but I haven't used them.) Hard part is you have to remember to put it out each day/night, and keep the batteries fresh. And then there's always the time you forget it's there and scare yourself... LOL

I have heard that bubble wrap will keep cats away from something, so maybe it works for dogs too.

I pulled the wall to wall carpet up in my den and put wood flooring in. It stopped them because they can't get a running start on that floor. They tried a few times but eventually gave up. They're both 12, one a mini poodle and the other a tiny toy....so now I make sure they have little beds all over the den that they CAN get to and they seem happy with that. Of course, bedtime is a totally different matter....they both sleep with me in my king-size bed! :)

ah but they like to be comfortable too. i just use a comfort on my couch.

Wide heavy duty aluminum foil may work, It makes lots of noise when they get on it and most dogs/cats don't like it. Also good for keeping cats off your counters.

I put a curtain rod on the sofa and the dog has not gotten on it since.........so when someone comes over they think I was cleaning or working with the curtains.....but Andy was a couch sitter.....now he won't go near it......and Andy is 10 so it's true dogs can learn new tricks......

I have 7 cats.....there is no way to keep them off my furniture, so I always through an old sheet over my upholstered pieces before leaving the house. While I'm home, they know to stay off, but coming home to a clump of cat hair is most telling!

just put a blanket on the couch when you leave and let the old dog nap in comfort.my dogs are allowed on the couch.

i throw a blanket or sheet across whatever i don't want pet hairs on, my DH uses mousetraps. The noise when they get activated scares them off, not getting pinched. You don't bait them, just set them.

My dogs go into their kennels when were gone. They are not allowed on the furniture and never have been. On our laps yes furniture no. It's enough to keep up with the dog hair on the floor and floating around on the furniture/tables with out letting them lay on it. I love the two we have but when their time comes that's it. We can't get anyone to care for our dogs with out them either getting sick or something when we want to go on a vacation. Hence it's been at least a decade since DH has gone out of town. He trusts them with no one and I feel the same way. Just not letting them on the furniture. Another reason we have no cats. I've had my fill of them about 25 years ago. I don't hate animals, I just don't really need them.