There are a lot of fraud-like situations, where there’s no fraud in the strictest sense of the term, but consumers feel defrauded. Let me give a few examples:

1. Price of a certain item is 225 (in whichever currency) at one outlet of a chain store in one zip code and 265 at another outlet of the same chain store in the adjacent zip code.
2. Price of a certain item is 100 when the order is placed on an ecommerce website. Two days later, before the item is shipped, the price of the same item on the same ecommerce website falls to 80.
3. Price of a certain item in a grocery store is 30. Price of the same item in a multiplex is 90.
4. Price of the same hotel room jumps up from X to X + Y between the first and second visit to the same Online Travel Agency (OTA) website.
5. One borrower gets a mortgage at 10%. Another borrower gets an identical mortage at 11%.

These are all examples of Price Discrimination. They may be sharp business practices but, in most jurisdictions, they are not frauds. (Caveat Emptor!)

Then there are many silly ways by which people will tell you to escape fraud.

EXAMPLE-1:

<https://twitter.com/s_ketharaman/status/1218508631051771904>

EXAMPLE-2:

<https://twitter.com/s_ketharaman/status/1099949672389640192>

These are noise.

In this blog post, I'll filter out the noise and give you my own set of guidelines to help consumers protect themselves from real fraud attempts:

1. There may be a sucker born every minute but you don't have to be that sucker.
2. Don’t give away information to every Tom, Dick and Harry who asks for it unless you’re getting something in return - immediately.
3. While cynicism may be frowned upon, a healthy dose of skepticism is advisable while approaching commercial transactions. Whenever somebody calls you and claims to be from your bank, ask them to prove their credentials before you reveal any personal information. Ditto for TELCOs, Utilities, etc.
4. While it’s perfectly fine to opt for convenience over security, always retain the final control over any transaction. When shopping or ordering food online, never pay along with the order. Always opt for cash / card on delivery. If you pay with order, you will need to chase the Delivery Agent. If you pay with COD, Delivery Agent will need to chase you. I’ve heard horror stories of people who have ordered food and paid online, not received the food for hours, and then, when they canceled the order, got neither the food nor the refund. More at Why COD Still Rules Ecommerce In India. (Sadly this tip is not applicable in geographies where ecommerce companies do not support Pay on Delivery mode of payment)
5. After years of buying and selling various financial products, I’ve jumped to the conclusion that Fixed Deposits and Stocks are the only two financial products that deliver predictability and value to the Consumer. All others, including Mutual Funds and ULIPs, are replete with gotchas and fineprint. It's not easy for the average consumer to navigate through their terms and conditions and benefit from them. More at Puzzle Versus Mystery: Who’s To Blame For The Great Recession.
6. Don't hand over a contactless credit card to a merchant. If he taps it on POS machine, the transaction will go through without a PIN or signature and you won't be able to verify that he has entered correct amount. Tell the merchant to enter the amount, look at the POS display, make sure the entered amount is correct, then tap the card on POS machine yourselves. More at PINless Card Payments – Innovative Or Harebrained?.
7. Visit ecommerce, online banking, stock trading, and other frequently visited websites by directly entering their respective URLs in the browser address bar. Don't Google them. If you do that, your search results might contain ads from imposters. By using phishing techniques, they can harvest your login credentials and steal your money / stocks. Or defraud you in some other way. In an egregious case of fraud highlighted in Never Ending Search For End Of Google Search, many people have lost all their bitcoins when they Googled "blockchain wallet" instead of visiting blockchain.info directly. For the uninitiated, blockchain.info is the URL of a leading cryptowallet wallet.
8. Whenever you sign up for a free trial, set a reminder to cancel the subscription before the end of the trial period. In this day and age of rampant #SubscriptionTrap, this should be common sense but many people still miss this and end up with huge bills - like this guy who set up a Google Cloud account with free credits for a hackathon and then forget to cancel the subscription and ended up with a bill for $4000.
9. Sign up for subscriptions of news, streaming video and other services only via Play Store, App Store, PayPal or some other third party website / app that allow you to cancel the subscription anytime. Many companies use the so-called Roach Motel dark pattern to make it easy to sign up but hard to cancel their subscriptions on their original websites / apps e.g. Wall Street Journal.
10. Notwithstanding all of the above precautions, $hit always happens. If you pay with a credit card, you can protect yourselves even in that worst case scenario. Since Credit card is a revocable method of payment, if you don't get the ordered goods or they don't work as advertised, you can dispute the charge and eventually get it reversed and get your money back. On the other hand, Account-to-Account Real Time Payments (A2A RTP) like UPI / NEFT / IMPS (India), FPS / PayM (UK), Venmo / Zelle (USA), AliPay / WeChat Pay (China) are irrevocable. If you pay with them, your money is gone forever.

The above list is based entirely on my personal experience. It's by no means exhaustive.

By all means, feel free to use this list but please be forewarned that it's not guaranteed to work under all conditions.

But, above all, remember that law enforcement may not always be in a position to help consumers in the case of many “frauds”. Click here  for more details on why this is the case.

Free markets offer a lot of choice and freedom to engage in commercial transactions. But, while nobody will say this explicitly, they also expect consumers to own their actions instead of seeking the government's intervention for each and every thing.

There's a good reason why Caveat Emptor has been a best practice since the times of the Roman Empire thousands of years ago!