Mark
Special Assessment can indeed hit you bad, it all comes down to how well the building is run.
It's usually a problem in older buildings as things age and need to be replaced, upgraded, etc... normally, monthly maintenance include reserves for the big things... Roof, elevators, painting, risers, etc... but often owners choose to waive reserves to keep maintenance payments low. i forgot the rules but in FL it takes either a majority or 2/3 votes to waive reserves...
that's fine once in a while, if other things come up that year, but in the long run it can be disastrous. Looking at the buildings history and how the reserves have been funded is a good idea and may help you avoid surprises...
then you may have special assesment because of damages, storm or others.
Some buildings are also better built than others. After Andrew in 92, the building i had a condo in was virtually undamaged even though many units didn't even have shutters (and it was in the north wall of teh cat 5 storm). Others, just a block away suffered heavy damage and were closed for days or weeks while ours had full services restored within 48 hours.
beware of older buildings, especially smaller ones. Those with mandatory shutters are a plus too.