Celebrities are also being tempted with luxury trips overseas and even "Instagram-able" picture opportunities on champagne-filled yachts.
Cooper — who manages Meghan Markle's sister Samantha — says many stars are accepting these offers as their salaries dwindle.
"Between 2013 and 2018 there was a steady growth in the number of men reaching out to stars and propositioning celebrities, but since the start of this year there has really been a dramatic increase in men wanting to hire celebrities for sex," he says.
"It's becoming more normal because fame is nothing like people imagine it to be.
"Many past reality stars are really struggling financially and have to either face the embarrassment of going back to a normal job or take their clothes off to maintain an income.
"I know of a number of former soap stars and reality TV shows like TOWIE and Love Island have been propositioned."
STARS SEEKING HIGH-END ESCORT OFFERS
Some desperate celebrities are even asking their agents to help them get extra cash through high-end escorting.
"I know of at least 10 celebrities who have asked their agents to actively pursue any leads that may give them high-end escorting opportunities," says Cooper.
"This includes a former WAG, glamour model, two female Love Island contestants, a male Love Island contestant and a TOWIE star."
He adds: "The offers are between $7k and $35k. There is often offers of luxury trips to exclusive resorts in Dubai and offering 'Instagram-able' picture opportunities such as endless bottles of champagne and yachts. It's genuinely worrying."
Lots of reality stars are constantly pictured in Dubai when their reality series end — though there is no suggestion any of them have accepted these offers.
$18,000 EVENINGS THAT START WITH DINNER
Exclusive escort agency Elite Models VIP says celebrities and so-called "influencers" — those with large public followings — can charge far more than other high-end escorts.
A spokesperson tells Sun Online: "Whereas the usual amount for an evening can be $3-5000, for celebrities they can charge about an average of $18,000.
"It's up to them what they do with the client in private."
Initially, stars on the agency's books will usually meet with their clients for dinner. But after that, they can choose how often they meet them and what they do.
"Some even start relationships from it, which is usually a sugar baby relationship. So yes, if they choose they want sex with the customer then they can," adds the spokesperson.
Before her time in Love Island 2018, Megan Barton-Hanson worked as an escort and dated sugar daddies — though there is no reason to believe she has had any of these offers.
"A lot of men will pay a higher fee for these women because they want to be seen with a celebrity on their arm, and they want to be with these people they've seen on their TVs," said the spokesperson.
"But also because a lot of clients are either super rich or high-profile people too — like footballers or big actors — so they want total discretion, and they get it from other celebrities."
Both the celebrity and the client has to sign a confidentiality agreement.
And the phenomenon of celebs pursuing X-rated opportunities isn't just female-orientated, as Cooper reveals male reality stars are turning to "Gay4Pay" opportunities — where they pretend to be gay to please clients, even if they're straight.
"There are at least three heterosexual male reality stars participating in solo or duo gay porn already on the internet," he says.
DESPERATE CELEBS SELL DIRTY UNDERWEAR
"There's also many famous men who offer 'extras' via DMs on sites such as Onlyfans — with some receiving oral sex on camera for as little as $700. Some celebrities even sell their unwashed underwear for as little as $300."
Former Love Island contestant Alex Miller has an active OnlyFans account where, for a small fee, fans can view videos "of him urinating and another of him masturbating while using an anal vibrator", according to the Daily Star.
Talent manager guru, Professor Jonathan Shalit OBE, whose clients have included Mel B and Kelly Brook, says he has also witnessed stars being propositioned.
"On the odd occasion, I've had people ring me up and offer ridiculous money for my clients to do things where they're clearly expecting more than just a cup of tea," he tells Sun Online.
"Some years ago, I had a well-known client who was in the Middle East on a corporate and they were then invited back to someone's apartment.
"Luckily, the person from my office who was with them realised they were on the verge of being compromised in that way, so they immediately got a cab to the airport."
Summer is a particularly busy time for celebrity escorts — as wealthy clients offer to take them away on holiday to Dubai, southern France and Spain, and on fancy yachts.
"The girls like it because it's glamorous, very exclusive, and they get paid well. It's not like seedy prostitution — they're getting luxury perks," says the Elite Models VIP spokesperson.
"For example, one of the girls went for a weekend on a yacht recently and was paid $35,000 for it. It's not usually a one-night thing, it's usually on a longer-term basis where a celeb has a client they meet once or twice a month maybe and they get treated well — lots of gifts, holidays, fancy dinners at hotels."
Echoing Cooper's comments about why celebs might turn to escorting, the spokesperson adds: "For a lot of them, especially those in (reality) TV and models, they don't actually always get paid that well. But because they are in the public eye, they have an expectation of living their lifestyle to a high standard."
'HE OFFERED ME $70,000'
After a graphic six-second sex tape of her performing an intimate act on ex-boyfriend Jake McLean was leaked online in 2014, mortified TOWIE star Lauren Goodger fled to Dubai.
But while she was there, a rich admirer offered her a staggering $70,000 for a night between the sheets.
Opening up about her sexploits in the Celebrity Big Brother house later that year, Lauren, 31, told how she thought the holiday would be her sanctuary from her sex tape ordeal, but instead things went from bad to worse when a millionaire propositioned her.
She said: "A guy in Dubai said, 'I will pay you 70 grand for one night, but you cannot tell anyone'." Lauren insisted she turned the extremely generous offer down, adding: "My mum went on the phone pretending to be my agent."
'I EARNED $90,000 AS A CELEB ESCORT'
Model and former UK I'm A Celeb contestant Sophie Anderton has revealed she worked as a high-class prostitute when her fame began to dwindle in 2004. The former Wonderbra girl charged wealthy businessmen $25,000 an hour for sex to fuel her drug addiction.
She told The Sun newspaper: "The first time, it was all over in two minutes. I lay there thinking, 'Is that it? For $25k, is that it?'"
The 42-year-old would drink a bottle of vodka every night and use cocaine in the daytime — and her boyfriend, Man United goalie Mark Bosnic, dumped her as a result. "The coke ran out, my cash card was rejected and my dealer was ringing up demanding payments. I knew I desperately needed money — now," she said.
Anderton was introduced to a sex worker who told her to dress sexily and priced her at $17,000 to $25,000 an hour. She slept with five men in total and earned $90,000 to pay off her drug debts and put down a deposit on a flat.
This article originally appeared on The Sun and was reproduced with permission.
