Millionaire fighters like Floyd Mayweather and Conor McGregor are the exception rather than the rule.

A lot of boxers and mixed martial artists (MMA) earn between £300 to £3,000 per fight, according to Business Insider sources.

Many moonlight as taxi drivers, bricklayers, or painters as journeymen and prospects receive £300 to £3,000 per fight

English fighter Paul Daley has multiple business interests which allow him to concentrate on training and competing.

Boxing and cage fighting are "lifestyle" sports — athletes do it for the love.

It is billed as the "billion dollar" bout. A coming together of one of the greatest boxer's ever, Floyd Mayweather, and UFC's biggest star Conor McGregor. Two athletes at the top of their earning potential.

Mayweather's 2016 earnings totaled $44 million (£34 million) according to Forbes. McGregor, meanwhile, made $22 million (£17 million). The cash fuels lifestyles of designer clothes, fast cars, and topless bars. And they flaunt it all on social media.

But these financial success stories are not the norm. McGregor was the only mixed martial arts (MMA) star to feature on the Forbes list of highest-earning athletes in 2016. Only three boxers made the ranking: Mayweather, Manny Pacquiao, and Saul Alvarez.

In 2017, only McGregor, Alvarez, and newcomer Anthony Joshua featured on the Forbes list. Compare that to nine soccer stars, 16 American footballers, 32 basketball players, and 22 baseball stars.

Now consider this: There are approximately 20,000 active professional boxers and over 1,000 professional MMA athletes in the world, according to figures from Boxrec, UFC, Bellator, and the World Series of Fighting.

A conservative estimate, based on previous Forbes reports on high-earning boxers and MMA athletes, suggests there are only 19 fighters capable of commanding annual salaries in excess of $2 million ($1.6 million). That's just 0.09% of fighters in the top earning bracket.

The reality is that the vast majority of boxers and cage fighters live from fight to fight.

Legendary journeyman Johnny Greaves (right) competed in 100 fights over six years. Scott Heavey / Getty Images

For journeyman boxers (adequate combatants who are brought in as cannon fodder for top prospects), paydays typically range between £250 to £1,000, according to numerous fighters Business Insider has spoken to over the past five years. A top prospect could command around £2,500 to £5,000 per bout.

Over the course of the year, a good novice-level boxer could be involved in six fights. This gives you a pre-tax salary of £25,000. Once you strip out tax and coaching costs, Business Insider analysis suggests that novice-level boxers may only take home £17,781 from their earnings in the ring.

Teenage heavyweight Daniel Dubois is the face of BT Sport's boxing coverage. Dan Mullan / Getty Images

There are some exceptions. Sources tell BI that rising teenage heavyweight Daniel Dubois, whose first bout was broadcast on BT Sport, is paid a monthly salary by his promoter, Frank Warren — regardless of how often he competes. MMA star Aaron Pico, said to be one of the likeliest prospects to be the next Conor McGregor, gets the same treatment from Bellator.

The long-term hope, for both Warren and Bellator CEO Scott Coker, is that the investment eventually returns dividends. That Dubois turns into the next Anthony Joshua and Pico becomes a superstar like McGregor.

But these monthly packages are uncommon. It is why fighters often turn to the gig economy to top up their earnings. They take on jobs as taxi drivers, bricklayers, or painters and decorators, just so they can make ends meet.

MMA star tops up fight earnings on the stock market

Step forward Paul Daley, one of the most battle-hardened athletes you can meet, thanks to 80 professional kickboxing and mixed martial arts (MMA) fights.

Paul Daley tops up his earnings outside of the cage. Jordan Mansfield / Getty Images

As his nickname 'Semtex' suggests, he is dynamite in the octagon. The 33-year-old is also open about having to make money outside of the cage.

Daley's recent contests have all come under the Bellator banner, a company known for paying more than UFC, MMA's market leader. Bellator declined to comment on its pay structure, but Rory MacDonald, a former UFC fighter, told us that Bellator "pay considerably more than UFC."

MacDonald is a championship standard competitor. Daley is a level below, but still an upper tier fighter. For his involvement at Bellator 170, when he stole the show with a flying knee knockout win over Brennan Ward, he is believed to have received $50,000 (£38,750).

More recently, Daley was outclassed by MacDonald during a show in London, in May. Despite the loss, Daley already has his sights on another high-profile fight as he scuffled with English rival Michael 'Venom' Page in a mini riot at Bellator 179 last month.

Clearly, paycheques are still heading Daley's way but the fighter insists that there is a noticeable difference between the figures reported by the media and what he takes home.

"There is a considerable percentage taken by the taxman, just like in other jobs," Daley told Business Insider. "Around 10% goes to my main coach and then another percentage is divvied up between my other coaches."

Daley has coaches for striking (boxing and kickboxing), for wrestling and jiu-jitsu (grappling and ground game), and for conditioning (fitness). Additionally, he'll pay other fighters to come to his Spirit Dojo gym, spar him, and help him train for an opponent.

Even if he contests three Bellator fights a year at $50,000 a pop, that's still a lot of expenses. So, he's inventive about where he makes money elsewhere. He stopped short of revealing his net worth and earnings, but did cast light on how he makes money outside of the ring.

He owns the Spirit Dojo in Nottingham, where he helps coach. He also teaches. "Teaching seminars brings money in like when rappers do concerts," he says. "I also sell merch [merchandise]."

The stock market and property are other interests. "I invest in stocks, I've got money in share funds, and I have properties I rent out in Nottingham," he explains.

Sarah Beeney, an unlikely role model for a cage fighter. Channel 4

Puff Daddy and Damon Dash are "positive role models" but another inspiration is slightly more leftfield. He says: "You know who else I always looked up to? [British TV presenter] Sarah Beeny. Man, I loved 'Property Ladder' on Channel 4. I even got her book last Christmas. You know, property is my game outside of MMA."

Fighting is a "lifestyle sport"

For most of the 21,000 pro boxers and MMA fighters, their sport is a "lifestyle," according to combat sports expert Gareth A. Davies."Fighters get pleasure from being in the gym," he told us. "Fighting is what they do naturally very well and I think, for them, there's a beauty in that lifestyle."

Davies compares MMA to niche sports. He explains:

"It's not a huge earning sport but from what I hear from fighters they are happy with the level of pay they are getting. MMA is still a young sport and a young industry. I equate it to surfing, snowboarding, and polo. They just make a living. Not all are big earners as they are all involved in lifestyle sports. The money is just a bonus to them."

Most fighters are not as rich as Mayweather or McGregor, but the sport enriches their life.