In addition to dog sitting, you could also offer to foster for a local rescue group to try out dog ownership. Fostering is a short-term commitment and it would let you test out life with a puppy or older dog.
I have two dogs, four cats, and have fostered puppies and large-breed dogs on and off for the past 5 or so years. I LOVE my pets and cannot imagine life without a dog or two. But I also agree that you should NOT get a dog unless you are 100% on board and financially ready for it.
Tara
living a crazy life with 3 boys
I am thinking now
of grief, and of getting past it;
I feel my boots
trying to leave the ground,
I feel my heart
pumping hard. I want
to think again of dangerous and noble things.
I want to be light and frolicsome.
I want to be improbable beautiful and afraid of nothing,
as though I had wings.
~Mary Oliver