I really think my dh has underestimated the work involved or the length of the commitment required.
He's not alone. I don't think anyone realises how much work a dog is until they have one as an adult and are fully responsible for it. Growing up with dogs doesn't really give you any insight into what it's like to care for one full-time!
We thought for two years before we got our dog and we had lots of criteria that had to be in place before we brought him home. Once those criteria were in place, we then started to look for a breeder (we always had a breed in mind). We read the books, looked after people's dogs, talked to people with the same breed and it was still a massive shock when we brought him home!
Don't get me wrong, I love him and wouldn't be without him but he's a lot of work. He sheds (and he's not massively high-shedding so far as dogs go), he's expensive (chews, food, jabs, flea/worming) and he needs a lot of time and stimulation. He gets two walks a day, everyday. Three days a week he goes to daycare (another expense!). He still needs brain games everyday, someone to play tug or fetch. He goes to weekly training class which is great for him, but involves commitment and expense (again!) on our part. On his walks he rolls in poo (and eats it), rolls in the mud, jumps in muddy puddles, barks at other dogs and pulls on the lead (he's only young).
I'm really glad you're reconsidering and I don't mean that in a bad way. I think everyone should reconsider dog ownership several times before going through with it! It's a long commitment, you need to change your entire lifestyle - days out, the school run, toilet training - you need to plan how you're going to cope with all of those things. You can't just spend the day at the zoo without considering the dog, for example.