Most screen doors don't need professional installation, unless you're not at all handy. Most magnetic options simply attach to the doorjamb using adhesive-backed pieces of Velcro or tacks, which won't prove a problem for most people. Hinged and retractable screen doors need to be fastened in place with tools. While most people might be able to do it without the help of a professional, it's better to pay someone who knows what they're doing if you're unsure.