ArcSite is described as 'easy-to-use CAD and sales presentation tool that helps you visually communicate to your team and customers so you can take on more clients' and is an app in the Photos & Graphics category. There are three alternatives to ArcSite for a variety of platforms, including Mac, Online / Web-based, Windows, PortableApps.com and SaaS. The best alternative is LibreCAD, which is both free and Open Source. Other great apps like ArcSite are Autodesk AutoCAD (Paid) and Dock Designer (Paid).
LibreCAD (originally QCad then CADuntu) is an open source 2D CAD application for Windows, Apple and Linux. It is based on Qt, which is a leading cross-platform application and UI development framework.
AutoCAD is a leading CAD (computer-aided design) software used professionally throughout architectural, electrical, mechanical and other engineering and design industries. It was once available under a perpetual license but is now accessed solely through a subscription.
Customized to the specific building rules of dock building companies, Dock Designer enables visual design in 2D where you can see your dock design in 3D and have instant access to accurate estimates, parts lists, blueprints, and much more.