About Us Since 1997, Mark Cullen Home Improvement has delivered quality workmanship and unparalleled service, at an affordable price. The satisfaction of our clients is what drives our continued success. We base our business off of strong Christian values. Our business growth is directly connected to repeat customers and We are proud to be the local home improvement company of choice for Baltimore county. Mark Cullen Home Improvement is committed to providing unsurpassed customer service with the absolute best home improvement value. We employ happy and knowledgeable people, and observing state and municipal building code regulations as well as upholding the highest ethical standards in the industry.