Now he is hoping The FA Trophy can help continue their meteoric rise – starting at Hemel Hempstead on Saturday.
Rangers produced the result of the First Round when they crushed Conference leaders Barnet 6-2 at the Hive in December. It pushed them into the last 32 for the first time in their history and also banked the Essex club £5,000 in prize money.
Hemel Hempstead v Concord Rangers
The FA Trophy
Second Round
3pm, Saturday 10 January
Vauxhall Road, Hemel Hempstead
Winners receive £6000 from prize fund
Their next test is against fellow Conference South side Hemel Hempstead on Saturday but Cowley has longer-term visions for the club.
He told TheFA.com: "This is the furthest we've been as a club in The Trophy and the prestige and money is massive for a small club like us.
"Financial reward is really important and we thank The FA for the prize money on offer. It can make a real difference to small clubs like ours.
"We're moving towards a full-time academy which would be a very big step for the club and its longevity at this level. When we compare the resources to other clubs at our level, we're miles off but we're trying to do things the right way.
"Having an academy will help us attract the best young players in the south east of Essex. Our chairman is fantastic and always invests money back into the club and we're looking to improve our club house further while we've had brand new changing rooms this year. A 3G training pitch is also an aim of ours.
"We've come a long way. We were in the Essex Senior League, Step Five, in front of about 50 people. Now we're in the Conference South averaging 300 people in our home games."
Alongside Cowley every step of the way has been his brother Nicky, who recently retired as a player due to injury but stayed on as assistant manager.
And not only are the duo inseparable for Concord, they are both PE teachers at the FitzWimarc School in Essex, where Danny is head of PE and Nicky is Head of Boys.
The Concord boss said: "We work together and have football together - we live in one another's pockets to be honest.
"He's just retired through injury but he played for us throughout the eight seasons. He's always had an input even towards the end of his career so it has been a natural progression.
"It's sport mad, 24/7 sport. It's what we love to do. We spend all day working with children at the school then we go home and head off to football."
So who is easier to control: the pupils at school or the Concord Rangers side?
"Good question," he said.
"They both have their moments."
