I'm so glad you're considering Austin....awesome Austin! In regard to your questions, I spoke with my mortgage broker who would like to communicate with you directly as there are several scenerios that apply and he has questions to ask to see how you would qualify for a mortgage. And yes, you can also rent. Please let me know and I'm happy to help.
As far as what taxes you would be responsible for you will have to pay real estate taxes annually (these can be included in your monthly mortgage payment if you so desire) and certain state and city taxes associated with getting your mortgage. To determine what the impact will be on your personal taxes you would need to consult with an accountant.
Finally, renting the home you plan on buying before actually purchasing it would have to be something the seller is open to. With so many properties up for sale right now, the more aggressive ones are offering buyers lease with option to buy contracts. A competent and qualified realtor would be able to assist you in finding these types of offers.
Robbins and Lloyd Mortgage
RLFunding at AOL.com