When I park at the airport, paying for the lost ticket is cheaper than three-plus days of parking. So if I’m there for longer than three days, I just say I lost the ticket and pay the fixed price.

If you've got a decent bit of land, find out what your state's requirements are for agricultural tax exemption. Significant drop in property taxes. Friend keeps six cows because that's one of the things that qualify you. She's bought hundreds of acres and built a barn that costs more than my house to keep her horses, which are not, per that state's law, for agricultural use. Adding six cows turned the whole operation into agriculture and saved loads each year on property taxes. Another friend sells about $2,750 in nursery stock from her greenhouse. 2,500 a year is the requirement in her state. It's not illegal. Slightly unethical because the point of the program is to help out farmers. Doing the bare minimum to qualify to save on property taxes is obviously not what they meant. This is the basis for many Christmas Tree farms.

Setting up an emergency fund to collect emergency donations. Then keep 90% of the money.

My late wife’s sister set up a GoFundMe during her cancer diagnosis without our permission, (we were financially privileged, especially relative to our friends we made on the cancer ward.) It raised 35k before we caught wind of it and forced her to shut it down. They kept all the money! Needless to say, I don’t still have a relationship with my late wife’s family—not for that specifically, but it is illustrative.

I've made tens of thousands of dollars opening bank accounts for the sign up bonuses. Some banks like Chase, I've had 7 accounts over the years.

Roth your kids. Tax code says they have to do age appropriate work, so they can't do bookkeeping, but they can be models the day they are born. License their image and likeness for 6k (or W-2 them if you have a small business that does payroll), put the money into roth, and invest in an index ETF.

My wife’s mom goes to the Dollar Store and buys hundreds of books for 1$, then she sells them all on Amazon for $15-$20 a book.

If you work from home, run an LLC and write off everything imaginable. A quarter of your home is your office. Write it off. Lunch out? Put it on the business card. Anything you buy that's tech-related. I've even known people who write off vacations, with the idea that if they got audited they'd just say they were meeting a potential business partner.

Buy an atm. Set atm fee to 10$. Get 100 bank accounts with atm fees reimbursed. Take money out of the atm every day from each account. Collect 10$ fees, 1000$ a day. There is no deception involved, so this would be a very difficult fraud case to pursue. However, very difficult to pull off without the right accounts, money up front, and people helping.

If you have a very elderly parent, gift them $18,000 of stock every year. In fact, if you are married, you can gift them $18,000 and your spouse can gift them $18,000. If you have two very elderly parents, that is $72k/year you can gift them tax free. The parent receives the stocks at your cost basis if you do it as a brokerage to brokerage transfer. When your parent passes, they give you the stock as an inheritance. But it comes to you with its value at the time of their death. So you never pay any taxes on the appreciation of the stock. That is the hack - avoiding any taxes on the stock appreciation.

Insider trading for congress people.

Make a profile of a hot woman saying you want a sperm donor, but it has to be done 'the old fashioned way,' and the person has to have specific ancestry and no genetic issues. To prove this, the donor will have to submit a genetic test, and link to 23andme. The link will be, of course, your referral link that gets you 20 bucks per person you refer.

Secure a conservatorship of a lonely elderly neighbor. Then pay yourself a conservatorship fee to manage them until they pass away.

Drag barbecues from people's yards to the curb. Once the barbeque is at the curb it's considered garbage and not illegal to take and resell for cash.

The betting apps have sign on bonuses. Something like bet $5 and receive $150 in bonus bets. Bet your $5, then put half of the $150 on one team, half on the other. That's a free $75 for ya. Not unethical at all since they are offering it, but figured people should know. That is of course, you’re able to stop yourself from gambling in the future.

Eat a few grapes for free at the grocery store.

Become a televangelist and get poor people to send you money to buy a mansion and a private jet because that’s what God wants.

Research the "Step-up in basis" loophole if you have any assets. Also, set up trusts to protect your assets. Also, if you're an independent contractor, look up all the legal tax deductions to lower your taxable income. For example, business expenses, solo 401k contributions, HSAs, etc. The rich get richer because the rich usually have financial advisors/lawyers that know all the legal loopholes to stay rich and get richer. Almost anyone can take advantage of these financial "hacks," you just need to find them and apply them.

I know a guy who took out a bunch of loans to attend dental school. He graduated, became a dentist, and applied for a bunch of credit cards. Used the cards to pay off the loans. Used the unmanageable credit to apply for bankruptcy, and had the debts mostly cleared. Then he had seven years of bankruptcy on his credit report, rather than decades worth of loan payments.

My aunt was a tax accountant and said if you donate a car to charity, the IRS will never audit it if you claim a value under $5,000.

Hire other people to make stuff and provide services for you and pay them less than they make for you. Oh wait...