The street runs for over a mile and given the number of retailers on the stretch, the competition is tough for everyone. The Spar store goes head to head with rivals including Mace, Londis and Premier.
But Trudy, who took over the store more than three years ago, is determined that one thing will make her stand out and draw customers down the long high street and through her doors - the best customer service.
"You can live and die by how you treat customers," she says. "Here, that is multiplied with the competition and the fact we are the farthest along the road towards the seafront, so we have to make sure we have a point of difference. From an early stage that was customer service, and I have drummed this into the staff."
The extent to which Trudy's staff have embraced her commitment to customer service is illustrated by their nomination last year for the Community Involvement Award at the Robert Wiseman Dairies' Neighbourhood Shop Awards. That they were nominated came as a surprise because they hadn't put themselves forward - their customers had.
Going on to win the award was the icing on the cake for Trudy, as was the glowing tribute from one of the national judges who visited the store: "I want to extend my gratitude to the staff at Spar Coombe Martin, who provided such a warm welcome and an excellent level of service and are worthy winners indeed."
Trudy says: "It was an amazing night and the best thing was that it was all such a pleasant surprise. I am very proud of my staff and the fact that we were nominated by our customers - that's the best thing. However, now we have set a high standard I don't want us to fall from that, because if we have impressed our customers it is very easy to do something that changes that."
The nomination was a double triumph for Trudy because when she first took over the store she thought her decision to become a member of Spar could backfire. "The store was run by a local couple, was half the size and had a strong local following," says Trudy. "I wanted to double the size and give it a more professional look, but I was afraid that the locals would think that with a new look there would be higher prices.
"I was sceptical and I think they were, too, of how things would go. I thought twice about going with Spar but, looking back, the decision was the right one."
The refurbishment took five-and- a-half months, but Trudy was keen to keep the store open throughout so as not to lose the local custom and give her a chance to build up a relationship with her new customers.
The move paid off and the locals now see the store as somewhere they go not only for their top-up shop, but also their weekly shop. Consequently, the store's turnover increased from an average of £8,000 to £16,000.
This almost doubles again when the summer holiday season starts and the many nearby campsites and caravan parks push trade to near the £40,000 a week mark.
But Trudy is determined that her local residents are looked after as well as the much-appreciated passing trade. She says: "Even in the busy season we still run home deliveries and try to support as many local events as possible."
She adds: "Don't get me wrong, I appreciate the summer trade and the boost it gives the business, but our local customers are here all year round; they are the bread and butter."
With that in mind, Trudy has tried to build up the store's offer gradually and to make it as varied as possible. "I didn't want to throw everything at the store right away, but I still wanted to make sure there was a wide range of products and services for the customers," she says.
"We have recently brought in a DVD section and added an ATM, plus we are trying to expand our fresh and chilled offer. However, that doesn't mean we are going to neglect other areas such as bake-off, which is very popular, and I am already looking at how we can make the most of its potential."
She is also keen to source fresh meat and cheese from local suppliers and says: "I would also like to do more of a fresh offer and maybe get a local supplier involved with this."
A further boost to Trudy's trade is set to appear on the store's doorstep, when residents move into the six new flats being built next door. For Trudy and her staff it is another chance to impress, but at the moment her priority is to concentrate on maintaining her high standards.
"I think the store is right where I want it to be in terms of offer and size," she says. "We have two stock rooms, so there is potential to maybe lose one of them if we needed to expand in the future."
Trudy and her staff have set a very high standard in all areas, which they are determined to keep up. "It has been a good journey getting to the point we are at," she says. "It's been difficult at certain times, but I believe the hard work starts again every day to make sure that our customers stick with us."
Location: Spar store, Coombe Martin, North Devon
Size: 1,500sq ft
Staff: 16 part-time, 1 full-time assistant manager
Average weekly turnover: £16,000
Opening hours: 7am-10pm, seven days a week
Strengths: Home deliveries, local produce, customer service