MINNEAPOLIS (WCCO) — Repair contractors were already gearing up to go after business within minutes of Monday’s hail storm.

Chalk that up to modern weather software that can point them in the right direction.

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When the skies opened up and the hail rained down, the damage was soon obvious. Stones, some the size of baseballs, were pelting windows, rooftops and siding from Watertown to Maple Grove.

“You see here we have holes in the siding,” said Edina contractor Charles Clutter, with Monarch Builders and Commercial Services.

Contractor like Clutter use a weather mapping app on their phones and tablets. It allows them to pinpoint exact neighborhoods where the most severe hail fell, and very likely where the worst of the damage will be found. It even shows the size of the hail stones.

“You’ve got Watertown here and you can see it’s three-and-a-half inches in diameter,” Clutter said.

Consumer advocates say it’s best to work with only licensed local contractors. Hiring out-of-state companies to do your repairs can be risky.

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“It’s what happens a year from now if there are defects or issues. They’re not going to answer the phone and not come back up here to do a $2,000 repair to make sure you’re a satisfied customer because you are one and done and they’re on to the next storm,” Clutter said.

Local ordinances require contractors to obtain a solicitor’s permit to go door-to-door, appealing for business.

“Homeowners insurance is made for this type of situation,” said Mark Kulda, with the Insurance Federation of Minnesota.

He advises that homeowners should obtain several bids.

“When there are people coming to work on your home, make sure to check for references and that they have insurance and are licensed properly,” Kulda said. “You want the best job done, and usually, local contractors have that taken care of.”

What matters in the end is working with a quality contractor who does quality work. Consumer advocates say referrals and references are always helpful when choosing a home contractor.

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A hail storm on June 10, 2017 was Minnesota’s costliest storm ever for insurance claims. Homeowners collected on $3.2 billion in hail damage repairs.