Great detail (you gotta have it!)....I'm wondering how you felt when someone asked you to remove the snail? Did you think it was a shitty job? Any fear? Or was it like: do I have to do this, why me? Or what feelings...?
The details you give of the warm and inviting home with polished floors is good - it's showing that this home (an aspect of yourself) is in good shape (doesn't need renovation or anything - is comfortable, polished). I'm wondering if something is going on with your own home right now? (snails carry their homes on their backs - but they are slimy little creatures inside...)
The fact it turned into a dog...hmmm...I always think of dogs as being a symbol of our conscious minds (cats are subconscious)....so perhaps you are actually conscious of what this dream represents?? Or....something about your own home is going to bubble up to your conscious mind verrrry soon...