Belleville-based Mainstreet Computers Inc. has been acquired by Convenient Payments Holdings LLC, a portfolio company of Beekman Investment Partners III LP. Mainstreet is a business software provider to the auto and flat glass industries.

Through its flagship product, Glas-AvenueTM, MainstreetTM offers an integrated software solution that enables its customers to quote, accept, and manage work orders, schedule technician jobs, manage inventory, accept payments, communicate with insurance carriers, and complete many other critical business functions.

“We are impressed with the MainstreetTM team and are thrilled to welcome them to the Convenient Payments family,” Convenient Payments CEO Casey Leloux said in a statement. “Our vision for Convenient Payments has always been to partner with software companies like Mainstreet, connect them to our Intellipay payment processing platform, and provide additional resources both to accelerate growth and support critical back-office functions, including accounting and finance, marketing and product development. Today, with support from Beekman, we took a big step towards achieving that vision.”

Mainstreet CEO Brad Rhoades added: “We look forward to working with Convenient Payments and Beekman. Their experience with businesses like ours as well as the resources they bring to bear are a perfect match for our growth goals. By pooling our resources, we strongly believe that both companies will be better positioned to deliver value-add solutions to our customers on a more compressed timeframe.”

David Carnahan, the founder of Mainstreet, will be an investor and strategic adviser to Convenient Payments going forward.

Beekman Principal Jim Clippard added: “We are excited to support Casey, Brad and the entire Convenient Payments team in building a diversified payments and software business with innovative and value-add service offerings. There are several significant growth initiatives underway at each business and the combination will accelerate execution of those initiatives. We continue to seek complementary software and payments companies who would benefit from additional resources to accelerate their growth plans.”

Convenient Payments is the eighth and final platform investment for Beekman Investment Partners III LP and the second payments technology platform for The Beekman Group, which is based in New York.