SAN FRANCISCO (KGO) -- As San Francisco faces a spike in retail theft, the ABC7 News' I-Team is looking into just how pervasive the crime rings operate on our streets and online.
Police say these individuals often plan months in advance how to steal, where to resell, and at what price. So how can you tell if what you're buying online isn't stolen?
VIDEO: SF man arrested after police seize nearly $200K worth of stolen goods from apartment
"These operations are hundreds of thousands of dollars and the venture into the millions when you put them all together," said San Francisco Police Sgt. Adam Lobsinger.
On Wednesday, SFPD arrested a man who was able to sell, stock, and resell $200,000 worth of stolen goods in his apartment. It turns out - cases like that are happening across the Bay Area.
"This one arrest from Wednesday could result in opening cases on several other open investigations and lead to several other arrests," Lobsinger said.
According to investigators, the mid-market area of San Francisco is seeing a noticeable spike in these fencing operations.
Organized retail crime rings - how do they really work?
Police say they often start small and involve using middlemen or a "fence," who steal and try to offload stolen items as fast as possible.
"They culminate in something like this, where we're arresting one person or (persons) and they're selling hundreds of thousands of goods online nationally and we know they got these stolen items from multiple people," Lobsinger said.
According to an analysis by the Senate Judiciary Committee, there is more than $500 billion worth of stolen and counterfeit goods sold online across the world each year. In some cases, it's the online retailers tipping off investigators. For example, SFPD Lt. Scott Ryan says eBay contacted them about Wednesday's fencing suspect.
"We followed up, there was no crazy undercover process to it, but we followed up and saw what they saw and took steps to work with everybody to identify who he was," Lt. Scott said.
EXCLUSIVE: New SF DA explains how she plans to clean up city, hold criminals accountable
So what's being done to crack down?
State Sen. Nancy Skinner (CA-9th District) introduced a bill that puts more responsibility on online retailers while tightening requirements for sellers.
"So the marketplace has to get information like their business license, the receipt of goods, those kinds of things to prove they are the owners of these goods in a legitimate way and they haven't been stolen," Skinner said.
Skinner's legislation, SB 301 already passed the Senate and is moving to the Assembly.
Investigators say these organized crime rings operate on everyday sites we all use like eBay, Amazon, Craigslist, and Facebook Marketplace.
RELATED: Man charged with running international car-burglary ring out of SF boba shop, DA says
So what should you look out for?
"Is it a seller who is brand new, they've never sold anything before, especially if it's an expensive purse, an expensive watch, something like that," said ABC7's 7 On Your Side's Michael Finney. "Or if it's bulk, if it's brand new, bulk, a whole case of aspirin, you have to ask yourself, where did they come up with a case of aspirin?"
Finney added other red flags are unusually low prices.
"If the items are too good to be true that should concern you," Finney added. "If they have too many of the items that should concern you. If they have three Rolexes and you're like what's up with that? Ask yourself, is this a normal situation?"
If you buy an item that's stolen, you could also be subject to legal prosecution. While that's unlikely, especially if you bought the stolen item unknowingly, keep in mind, that legally it is not yours.
If you're on the ABC7 News app, click here to watch live