Hidden away on an unassuming industrial estate, to the south of Gravesend, lies the home of the world's biggest online record store; a haven for rare and collectible items spanning the generations.

While it may not look up to much from the outside - trains trundle along the railway tracks to nearby Meopham station just yards away - inside it is, to many, a palace of dreams - with row upon row of bulging shelves containing more than a quarter of a million sought-after items from the world's biggest names.

It is to an avid record collector what Willy Wonka's factory was to a chocolate aficionado.

This is the home of Eil.com; a company which has long boasted a global customer base and one which it has carefully cultivated over the years.

If you're after a rare Beatles first edition album in tip-top condition, or perhaps a Madonna picture disc, then the chances are this is where you'll look. After a tour programme, platinum disk, signed album? Then step right up,

It is a collection built up of new rare releases from around the world and carefully curated collections bought from house clearances or collectors looking to cash in.

"One of the craziest collections we bought was an Olivia Newton John one," explains co-founder Julian Thomas.

"It was a collection from someone who had just died and their relatives called us in. The house was literally stacked floor to ceiling with Olivia Newton John stuff in every room. It was mind-boggling. Records, posters, memorabilia - everything you could think of. If it had her name on it, it was here.

"It took about six van loads to get it back to us. She had a hit single called Sam and there wouldn't be just one or two copies, there were 200. And it was the same of every UK single. Then foreign singles and between five and 25 copies of each. There were thousands and thousands of records. There was an awful lot of dross but amongst it all were several highly collectible items."

And it is that diamond in the rough which has fuelled the firm's growth, courtesy of its expertise in what is now a hugely competitive market. Today it employs 28 staff. Not bad in an era where the mass consumption of music today tends to neatly side-step the physical product.

It was all very different when Julian Thomas and co-founder Robert Croydon first met - as eight-year-olds at Wrotham Road Primary School in Gravesend during the late 1970s.

Then the 7"-single was king and records were the main currency.

After attending different secondary schools - Julian to Southfields then Gravesend Grammar; Robert to St George's - they were reunited at college in Horsted ("it’s since been developed into a housing estate," explains Julian) - where their mutual love of music got them thinking.

"I loved things like Frankie Goes to Hollywood and anything on the ZTT label that Trevor Horn and Paul Morley set up," recalls Julian of what ignited his interest.

"I loved the whole thing of buying the 12" and not knowing what remix version you were getting.

"When it comes to collecting, it's not necessarily the acquiring the stuff, it's the fun of chasing it, searching it, researching it and learning about it. It does get a bit trainspotter-ish, but when you're that age and it's all hyped up, it was very exciting."

ZTT was certainly a label which knew how to exploit its customer base. Cleverly hyped and artistically delivered, one of Frankie Goes to Hollywood's big hits of 1984, Two Tribes, for example, boasted a slew of different 12" versions, alongside the obligatory picture discs, which sated the appetite of fans and, of course, helped it stay at number one for nine weeks.

"The difference then," Julian explains, "is that things weren't readily available. So if you wanted to hear those versions then you had no choice but to go out and physically find that record. You couldn't just tap it into a search engine or bring it up on Spotify. It was very different to how things are now."

So at the tender ages of 16 they set up their own fledgling mail order service. They would snap up copies of records and then sell them on for a profit. Helped, in part, by a record company practice deployed back then to help shift their products up the charts.

"We would go from college to the Pentagon Centre in Chatham,” says Julian, “and back then there were several record shops there.

"Because the labels were doing this chart-hyping thing, which we didn't really know at the time, if a record shop ordered a certain amount of stock, they'd get several times that amount free. So when a 12" was supposed to retail for £2.99, those stores which were putting the biggest numbers through the chart machines would get special deals so could sell them at £1.49 or £1.99. So you'd go down there and effectively find you could get the records at half the price of other stores. We ended up buying them from our pocket money with a view to turning a profit."

Placing an advert in what, at the time, was the record collecting bible - Record Collector magazine - what started small selling just a handful of items quickly snowballed.

Selling records from their bedroom, the pair got themselves jobs - Robert working in the City of London and Julian at commercial estate agencies in Maidstone. But at night, the record selling was all consuming.

"That carried on until about February 1989," the co-founder explains, "where we got to the point where we either give up the day job and have a go at selling records full time or give up the records.

"We were both getting to the point we'd spend all day at work, then come home in the evening and deal with telephone orders from 6pm to 10.30pm.

"Then it was a case of packaging up stuff you'd sold to people and trying to track down things people had asked to get from them. And pre-internet, that was all down to making phone calls and looking in adverts.

"We were completely skint, because anything we earned from our jobs got spent on more records. We were both living with our parents - so we had no overheads - it was really a case of it being an opportunity. We were 19 when we decided to go with the records.

"We would probably have been a lot wealthier doing our old jobs than as a record dealer but I don't think I'd have enjoyed it as much."

With the founders' parents each lending them £1,000 as start-up money, Esprit Mail Order was born (it would morph into Eil.com in the late 1990s when they discovered the Esprit web domain name had been snapped up by a fashion brand of the same name, so they went for the initials of their company - Esprit International Limited).

"We repaid our parents, with interest, within a couple of years," Julian says. "I often look back and wish we could have borrowed £50,000 to get us started, but that wasn't realistic at the time. Our growth has all been organic and self-funded."

First starting life in Gravesend, they have been in "ever-expanding buildings" in Meopham since the early 1990s.

And, just like then, there are some familiar names in the records which remain most in-demand from buyers - 60% of which are overseas.

"The biggest selling artists," Eil.com's boss explains, "are the Beatles, Stones, Led Zeppelin, The Who, Jimi Hendrix, Pink Floyd and Bob Dylan.

"But our top-selling items are led by what we buy. We bought a huge Prince collection a couple of weeks ago, and that stuff has been flying off the shelves as soon as we add it.

"I bought 2,000 Duke Ellington LPs recently and thought we would have our work cut out trying to shift it, but we've sold a tonne of it.

"We found a box of the Arctic Monkeys' first album - these were in an original box from the manufacturer, with the date they were printed on, so definitely first pressings. Bearing in mind you can buy their debut album for £15 online, we sold the whole box with each record selling for £125 each. And they sold within 48 hours. There's an appetite for things like that."

And it has been a case of the business evolving over the years as the way - and destinations - we buy music changed.

Julian adds: "We've dabbled in buying new stuff - we had a period where we were doing quite a lot of that, but once Amazon came along into that marketplace it was not viable. It was getting to the point where you'd order 100 Robbie Williams albums from EMI and they were cheaper to buy, retail, on Amazon than we were getting them at dealer price. Once that penny dropped we stopped.

"We've considered opening a shop and it's something we keep coming back to. We had a dabble in Gravesend and it was mainly new releases and cheap over-stocks but it was probably the wrong time to do it and the wrong location. All the record shops were closing and closing for a reason.

"When eBay came along, rather than your competition being professionals, it was anyone with a record and an internet connection. So from finding certain records among a bunch of dealers, eBay meant all those collectors could feed them back into the pool, and between themselves, so they didn't need the dealers - they could cut out the middle man.

"That changed things, but made it more important to build a reputation, which was trusted. People want to know if something goes wrong, you'll rectify it. Just old-fashioned customer service."

While the business continues to thrive, it has been one of many to be hit by the impact of Brexit.

"It didn't do us any favours," Eil.com's co-founder admits, "most of our European customers simply stopped ordering - about 80% in fact - as they were faced with duty, local VAT and admin fees to get items sent to them. It just made it unviable. And they're not coming back."

But what the changing world takes with one hand, it gives with another. The lockdown and enforced closure of bricks and mortar stores last year saw sales surge for the online retailer and it says the future is bright for a branch of the entertainment industry which has changed beyond recognition over the last 30 years.

"When people say vinyl is making a comeback and we must be doing really well - and I hate it when people call it vinyl, they're records - we never stopped selling records. That's what we've done since day one.

"When records started to reduce in the 1990s, all the records up to that period didn't suddenly become obsolete or less interesting. They may have been to a certain sector of music buyers but they didn't go away. But they did from the high street."

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