The necessary functionality is there to create a good comp map just by clicking "create map" and using it. If you wanted to support it, there's a 3 day free trial and it's $20/month for increased options and $100/month for probably large scale business solutions.
I've used Google maps, and just save the location for a long time. What I don't like about Google and Bing is that their maps include all the business names, which just clutter the map up when you're working in close. Google Earth Pro is hard to read, but accurate
I just figured out that one of the Counties I work in (L.A. County) has a GIS that allows markups, and which includes various base maps with good detail, no business name overlay; and in the L.A. County system the map extends across the entire US. You can build the map in one "basemap" and switch between them to find the one that is easiest to read. Build the map online and use a screengrab tool to save as a jpg - Pretty fast and simple if you can find your locations. This map is an area in Orlando FL, and the detail pic shows the individual streets in close