CHICAGO (WLS) -- Thursday is the last day for tax buyers to bid on delinquent tax bills in Cook County.
The Cook County treasurer's office reports more than 45,000 unpaid tax bills are up for auction this week.
Who are the tax buyers and why are they in this business? There is a wide array of them, from first-time bidders to seasoned veterans like John Bridge.
"We're just investors. We're not evil guys," Bridge said.
He and nearly 300 tax buyers are bidding this week on overdue tax bills. Bridge has been in the business 23 years.
"Tax buying is a necessarily evil. A lot of people look at us as bad people and we're really just investors. We're the collection arm for the county," Bridge said.
In fact, this week's tax sale totals $130 million in unpaid taxes for the year 2015.
The last five tax sales, tax years 2014 back to 2010, have generated nearly $365 million for the county.
"The system works and it forces people to pay the county," Bridge said.
So who are the biggest tax buyers? ABC7 analyzed the last five sales.
The top 10 tax buyers make-up two-thirds of the entire sale. Most are Chicago-based companies, with each spending about $4 million per sale.
Veteran buyers say they make 8-10 percent on their investment, some say it can be as high as 20 percent.
While Bridge says he has spent $700,000 on this week's tax sale, there are dozens of tax buyers like Val Densmore who started with as little as $1,600.
"If those taxes are not paid, then there is a deficit to the county, so someone has to be accountable for that," Densmore said.
And tax buyers have different goals. Some target vacant and boarded up properties.
"I would like to get some properties, fix them up and maybe learn how to do flipping," said William Girdwain.
Although we've heard a lot about homes on the South and West sides, property owners who haven't paid their taxes can be found in all corners of the county.
"You see this in the rich houses too. I'll see somebody that has a $35,000 tax bill and they're not paying theirs either, which means they don't have the money," Bridge said.
If a tax buyer purchases your tax bill, you still have time to pay your taxes plus interest during the redemption process.
The earliest you can lose your home would be in 2.5 years and the courts oversee that process.
Veteran tax buyers say the vast majority of property owners end up paying their taxes and about four percent end up losing their homes.