My old company has asked me if I would like to be a freelance designer for their landscape design business this summer. They have a full time designer, but are getting too much work. I accepted their offer, but, as I am working a full time job, I need to use my time efficiently. I have always hand-drawn site plans, but have been thinking about investing in a software program that can do this--particularly to make revisions an efficient process. Any recommendations for something relatively inexpensive that will serve my purpose? The rendering/elevation modeling is nice, but the site plan is the most important function I am looking for. Thanks in advance.