Adoption?

I have always been a supporter of animal adoptions, but I’ve never been involved in one myself. I’m not sure what to expect from new animals, but I want to give one the chance to be a loving pet. We brought home a dog today to see how well he would fit with our family. So far, it’s a yin and yang situation. We love him. He’s sweet, cute, energetic, and loving. The problem is that our cats hate him. We expected some issues with our cats and a new dog, but it was ridiculous. Our smallest cat actually chased him down and attacked him in a corner. After this, I completely assumed that we wouldn’t be able to keep him but then he swayed my opinion again. He started to calm down a bit and then he totally surprised me by climbing up on the couch and quietly laying with me. I’m torn now. Do I give the dog a chance and risk losing the love of the cats, or do I give the dog back hoping that someone else with a calmer house will find him? I worry that his excitement will ward off other adoptive parents so I feel like I should keep him, but we’ve had our cats for 3 years and they’re very comfortable with our situation. Another worry that we have is about the size of the dog. He’s much larger than any other dog we’ve ever owned before, and we can’t even find space for his kennel in our animal room. It’s not that I’m indecisive at all about the idea of having a dog, it’s just that this dog in particular worries me. I would love to keep him, but I just don’t know what to do for the well being of my other animals. The guilt is already kicking in, and I don’t even know what I’m going to do yet.