Not every hail car is a PDR car. Some storms leave a panel with countless dents; others leave dents so close together that the metal between them is stretched and wavy. In that case you might push the dents out, only to have them pop back later.
Decide at the quote, not after you accept the job. A vehicle that is too far gone can tie up days that could have repaired several easier cars, so efficiency and profit drop sharply.
If the cost gets too high, other methods such as conventional repair or push-to-paint are the right answer. You may lose the job, but you keep your reputation and your time.
Go deeper: this tip comes from the PDR eBook. See what is inside the eBook.
Prefer hands-on learning? See training dates. More PDR tips.