Last night’s City Commission meeting ended up sounding like a diet soda commercial, at times. The big phrase of the night was “net zero.” You know, like zero calories but all the same great taste. But city commissioners weren’t selling soda. They were selling a $2.25 million land purchase for a new police headquarters building.

As we reported, commissioners approved a letter of intent to buy about 47 acres of vacant ground from Hallmark Cards along McDonald Drive. There was no drama in whether commissioners were going to approve that deal. Staff members had negotiated about $1 million off the asking price for the ground, and commissioners like its relatively central location. But even with the reduced price, the Hallmark site is still the most expensive of any considered by the city. Two of the sites were on property already owned by the city — one across the street from the county jail in VenturePark and another near Sixth and Wakarusa — so there have been questions about why the city hasn’t pursued one of those lower-cost options.

Commissioners have said the central location of the Hallmark site and the fact it has been listed as the preferred site by Police Chief Tarik Khatib were big factors. But commissioners didn’t stop there. They also said they were confident the land could come at a “net zero” cost to taxpayers. That’s because the city only needs about 15 acres of the 47 acre site, and the city thinks it can sell the remaining acreage to help offset the costs. By the end of the night, though, it was clear that statement needed more review.

So, here’s a look at some of the details:

• The idea of net zero costs to taxpayers is a projection, and it is one that still will be uncertain when voters go to the polls in November. Commissioners won’t have all the necessary land deals in place to completely offset the $2.25 million purchase price by November. Voters will have to put some faith in the future real estate market.

• Part of the proposed sell-off of land has included the idea of a privately operated family fun center that includes electric go-karts, mini-golf, batting cages and other outdoor activities. When the project was proposed for a West Lawrence site, neighbors came out in strong opposition. On Tuesday, the president of the Pinckney Neighborhood Association said residents would want to hear a lot more about this fun center idea. They may have concerns as well.

• The city won’t be able to recoup its costs simply by selling the excess property off the Hallmark site, City Manager David Corliss confirmed. A big part of the plan is for the city to sell the West Lawrence building that currently houses a portion of the police department. The city hopes to get $2 million or so for that office building. That sale won’t happen until the police department has moved into its new building, so we’re talking a couple of years.

• How you account for the sale of the West Lawrence building is important. That’s because the city would sell the West Lawrence building regardless of where it decides to build a new police headquarters building. So, if the city gets $2 million for the building, that is $2 million that could be used to reduce the project costs at any site.

Here’s how the math on that works: The city is proposing to build a $25.7 million building. That figure doesn’t include land costs, so at the Hallmark site, the project is about $27.9 million. But before you can say “low-calorie delight,” commissioners are reminding you the ultimate price will be $25.7 million because they’re confident they’ll recoup the $2.2 million land purchase costs. But at the VenturePark site, for example, the city also plans to build a $25.7 million building. The city already owns the property, so there are no land costs to add onto the project. The city also would still sell the West Lawrence building for an estimated $2 million. It would have those funds to reduce the cost of the project to about $23.7 million.

It is not inaccurate for the city to say the Hallmark site comes at a net zero cost to the public, if their assumptions about future sales hold true. But if people hear the net zero argument and assume that means the project at the Hallmark site won’t be any more expensive than the project would be at one of the city-owned sites, that is a bad assumption.

Now, it is important to remember that price and value are not one in the same. When confronted with the math above, Mayor Mike Amyx’s response was that he’s still convinced the Hallmark site is absolutely the best one for a police headquarters location. So, that will be one of the tasks of city officials in the coming weeks: Help the public understand the difference between price and value.

It will be an interesting election to watch. The police department has a compelling story to tell about issues of overcrowding and outdated workspaces. But even supporters of the project acknowledge that the public goes into this election with some concerns.

There’s a group of citizens who have started to informally campaign for the police headquarters project out in the community. Members of that group last night told commissioners the two concerns they most frequently hear are: 1. Why is the police headquarters building coming after the Rock Chalk Park recreation center and the new public library? 2. Why is the city buying an expensive piece of ground instead of using city-owned property for the project?

Those will be key questions supporters will attempt to answer for voters before November. It is an important development that a citizens group already is forming in support of the police headquarters issue. A strong citizen’s group is definitely part of the formula for a successful election in Lawrence.

So, voters, get ready to hear a lot more about this issue. Or in other words, let the calorie counting begin.

In other news and notes from around town:

• If keeping up with Lawrence firefighters is more your thing, good luck with that right now. Getting an update on wage negotiations between the city and the firefighters union has proved difficult. The negotiations have been at an impasse since just before Independence Day, and when I asked for an update earlier this week, I was told there wasn’t one immediately available. The city and the union have agreed to communicate to the public only through joint statements, so I thought perhaps it was just a logistical issue that caused the delay on Monday.

But I asked again for an update on Tuesday, and was told there was still not one and there was no timetable for one to be provided. It sure appears that the city and its firefighters union are so at odds that they can’t even agree on how to provide a simple update to the public.

I can’t even tell you with any certainty what the two sides are butting heads about. In early July, the firefighters union said a study has been prepared that shows firefighter wages are about 8.5 percent below those of peer communities. City officials disagreed with that assertion. I’ve asked to see that study, but have been denied access to it by city officials.

Ultimately, I expect this issue to come before the City Commission. Even though commissioners have approved the 2015 budget, they technically could still approve a raise for firefighters. The money, though, would have to come out of someone else’s line item, or else would have to come out of the city’s reserve fund. That doesn’t seem to be likely.

I’ll provide you details when I get them, but at the moment, the takeaway seems to be that the city and its firefighters aren’t getting along very well.

• On a sunnier note, the city has received word that it has won a grant for a solar energy project. Prairie Park Nature Center has been chosen by Westar Energy as one of 15 locations that the electric company will pay to have solar panels installed.

The solar panels won’t only reduce the center’s electricity costs, but also will be used as a learning tool. Plans call for a kiosk to be installed inside the center, 2730 Harper, that shows how much electricity the panels are producing at any moment. Other information about solar energy also will be provided.