Re FMV, you should note that the IRS is not obligated to accept anything less than an appraisal by a certified real estate appraiser for that component. Odds are you will hear nothing if you use your own methodology, but you need to be prepared to substantiate the value (again, a formal appraisal is generally the more prudent route).
Re your claimed casualty loss, you might want to consider your time frame with regard to your ownership of the condo and any plans for the property in the future. You should note that when you sell, you will have to reduce your basis by the amount of the casualty loss you claimed.
Finally, you should consult with a local tax professional who is well versed in dealing with casualty losses, for both personal-use and business property.
