Gaining access to a boarded house

[Paul Zimmermann]

I have written permission from an owner to go into their house to see it before making an offer as a short sale. However, the house is boarded up and the owner now lives across the country.  Any thoughts on how I could legally get into the house? Can I remove (and then reinstall) the board myself and use a locksmith to get into the doors? Should I involve the town? Thanks in advance for any advice