PEABODY – Data collectors will be visiting Peabody homes during the next several months in an effort to come up with the city’s most accurate property-tax assessment in 10 years, according to Peabody city officials.The city is embarking on a full re-evaluation of Peabody’s property values beginning next month, an undertaking that will last into the summer, said Frederick Martini, Peabody’s chief assessor.If the city decides a home’s value has gone up, taxes for that home will likely go up as well, Martini said.Martini said he doesn’t expect tax rates in Peabody to change drastically with this reassessment, as median home values stayed static from 2010 to 2011.But there’s little doubt Peabody residents will end up paying more in property taxes, even if their home values dropped, he said.”Whether the values go down or up, you’re probably going to pay more taxes, it’s just a question of how much,” he said.Patricia Schaffer, the city’s finance director, explained that the property tax rate depends on the amount of taxes the city can levy each fiscal year, which is determined by the city’s annual budget and how much city officials need in taxes to pay for it.Massachusetts mandates cities re-evaluate their property values every 10 years to ensure residents and business owners pay an accurate amount of real estate taxes, Martini said.For this re-evaluation, Schaffer said the city spent $600,000 in cash reserves to hire a private contractor to collect information about every commercial and residential property in the city.Employees with Tyler Technologies, a Connecticut-based assessment firm, will knock on the door of just about every home and business in Peabody, said Eric Henderson, the project supervisor for Tyler Technologies.He said the employees will walk through a home in less than 15 minutes, in most cases measuring square footage, taking note of an added back porch or updated kitchen and snapping some photos.He stressed the employees are collecting information and not making an assessment of the property’s value. City assessors will crunch the numbers after all of the data is in, Martini said.Henderson and city officials said this reassessment shouldn’t cause anxiety among homeowners, because it’s meant to even out the share of the tax burden.”As a property owner, it’s in your best interest,” Henderson said. “You feel better knowing you’re being taxed equitably.”Peabody residents have their property values reassessed based on sales numbers every year, with a more thorough update every three years, said Schaffer.Peabody city officials said this re-evaluation will work best if everyone in the city participates. They said employees for Tyler Technologies will start knocking on doors the first week of February. They will wear a photo identification card with their name, phone numbers to the Peabody Police and the city assessor’s office.The city will also post neighborhoods where the contractors are expected to be collecting information on its website, www.peabody-ma.gov.Amber Parcher can be reached at [email protected].