Occasionally we get a post about mounting a single unit, affordability, how much is needed, don't fish much, the reasons why are numerous and not the issue here. I have a friend who only mounted one unit on his boat, it was all he wanted, he mounted it on a Ram mount at the console so he could just swivel it and occasionally check his depth, he caught fish, and quite a few. I've seen guys who only had one and it was mounted ate bow, same deal, it's the way I first started.
The main thing is that remembering the distance from the transducer to where you are in the boat, that's an important issue, if ignored you could be showing fish that are actually up to the length of the boat, an inch is good as a mile in this case.
If it's affordability you can advantage of sales, especially if a certain model is being discontinued or buying a Factory remaned, big savings there.
Rodney
Some great points and advice here ~c~