For a Key West Police Department patrol car, a professional career on the streets is eight years maximum.

Then they're replaced by this year's model.

Key West police have a fleet of 110 vehicles, of which 84 are marked patrol units with lights and the department's seal and motto: "Protecting Paradise." The rest are sedans used by detectives and cars issued to employees.

On Tuesday, the City Commission will likely approve Police Chief Donie Lee's request for 22 brand-new Ford Interceptors at a grand total of $567,602.

The request is practically an annual one, said city spokeswoman Alyson Crean, as the department staggers its purchases in groups of 20 or so.

"It's like an expiration date," said Crean. "As they age out, we replace the cars, so we're constantly having a fleet that runs. Some of these cars have put a lot of miles on them in seven or eight years. They're not breaking down. We give them a full life span."

The Ford Interceptor is a new platform designed to replace the traditional Crown Victoria and Chevrolet Impalas that are 2004 and 2005 models.

All 2013 Ford Interceptors, the car order is: 10 marked sedans at $25,813 each; two marked SUVs at $27,177 each; nine unmarked sedans at $25,344 each; and one unmarked SUV at $27,022.

The marked vehicles would come from Garber Fleet Sales in Green Cove Springs, Fla., while the remaining unmarked cars are available from Duval Ford in Jacksonville.

Key West was allowed to piggyback on the city of Jacksonville's upcoming order for police vehicles.

That means that the city doesn't have to spend money soliciting bids for review, but can join with Jacksonville and save money by buying in bulk, said Crean.

Duncan Auto Sales in Key West was offered a chance to bid but declined, saying in a Nov. 1 email that it couldn't due to the number of accessories required for each police car.

Police cars and SUVs have to meet Office of Law Enforcement Standards, which the Interceptors have, said Chief Lee.

The policing gear adds to the base price of a sedan, which is about $22,000. The light bars with full LEDs and alley lights cost $2,599 apiece.

One interior "prisoner cage with sliding window" runs $789, according to a Duval Ford government sales invoice.

"As in fiscal year 2011/12, the use of the Ford Police Interceptor package has proven to be reliable and mechanically superior to the older Chevy Impalas still in use by the department," said Lee in his written request to City Manager Bob Vitas dated Dec. 13.

Lee warned that leaving 7- and 8-year-old cars on the streets would result in "increased public safety risks and increased cost to maintain a fleet past its useful service life."

At times, a Key West police cruiser has its career cut short by a crash.

Also on Tuesday's agenda, the commission is asked to approve the "disposal" of a 2009 Crown Victorian deemed a total loss after a July 5 collision.

The sedan, bought for $24,000, racked up 20,664 miles, according to the adjuster's paperwork filed with Lee's request.

The police officer wasn't at fault, so the city put in a claim to RIS Rental Insurance Services Inc., which offered $13,700 to take the car.

gfilosa@keysnews.com