The motors division saw turnover go from £316.8 million to £321.7m with coach hire rising from just short of £23m to almost £25.4m.
According to accounts filed at Companies House, the increase in turnover helped to improve pre-tax profits from £10.5m to £12.2m in the 12 months to March 31, 2013.
Writing in the accounts, the directors said: "Despite difficult trading conditions as a result of the general uncertainty in the economy the company is in a good financial position at the end of the year.
"Sales in the motor division have increased by approximately 1.5%. Sales in the coach hiring sector have increased by approximately 10%. The trading results of the group have benefited this year by the acquisition of Douglas Park (Properties) Limited on 19th March 2012. This subsidiary has contributed profit before tax of £879,794."
The directors warned business conditions were likely to remain tough.
They said: "As for many businesses of our size, the business environment in which we operate continues to be challenging. The car market in the UK is highly competitive and margins continue to be tight.
"We are also subject to consumer spending patterns and consumers' overall level of disposable income within our economy."
Secured debts narrowed from almost £50.1m to £43.5m but more than £30.6m of that is asset-backed borrowing related to vehicle stock loans plus hire purchase agreements linked to the coach fleet.
Average staff numbers dropped slightly from 1111 to 1104 although employee costs increased from £27.4m to £28.2m.
Directors' remuneration edged up from £464,412 to £518,010 with the highest paid seeing emoluments growing from £99,667 to £102,168.
The accounts state the interim dividend was flat at £4.9m.
The directors said they would continue to look for "opportunities to expand the company's core business".
In June this year the company made its first foray into motorcycle sales with a 10,000 square feet Douglas Park BMW Motorrad dealership.
Park's was founded in the 1970s as a coach and bus operation before expanding into motor sales in 1977 with a Datsun dealership.
The bus arm now has more than 120 vehicles, while motor sales are run from dozens of sites covering brands such as Kia, BMW, Bentley, Citroen, Fiat, Honda, Jaguar, Mini, Nissan, Renault, Saab, Skoda, Suzuki and Volvo.