I think you should go for it! Like you pointed out, renting is not much cheaper, and:
1. you have to abide by the rules of the landlord/lady (no pets, no dogs, etc. etc.)
2. rent money is thrown away. Mortgage money gets you equity, and a house in the long run.
3. Apartments tend to be small (at least they are in this area). Many times a single room with a bathroom runs $750 a month.
4. If it doesn't work out and you can't swing it financially, you can always sell it.
5. You can't spruce up an apartment the way you would a house. When we rented, we couldn't hang anything on the walls nor could we paint. Everything was white, white, white.

Just my .02 cents

One more thing, if your roomate moves out, you can always advertise to get someone else. Especially if you allow dogs, I'm sure you would be able to rent it quite easily.