I would honestly sit down with an accountant and attorney and go over each and every property in my portfolio. If you have financing personally guaranteed by yourself, and you find it a better business strategy to "walk away", it makes it much easier to do after the first one.
Why would you walk away? Well, does it make sound business sense? How much money would you be paying out and not seeing a return? If you are making a return right now, how much more could you make by putting your money somewhere else? (by buying a different property as current market rates)
Each person has to make a personal decision about if walking away from a mortgage is something they can do. For some, it is a clear cut business decision, while others look at like they have made a personal promise to the bank that the must uphold. Only you can know the answer the that question.
If you decide to walk away, a competent attorney should be able to guide you through the legal process and may be able to dispense of the unwanted properties through deed-in-lieu or short sales, saving most of your credit.
Good luck to you. You have several decision to make either way.
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