In four years I have only come across two stumps I couldn't get to so far. Here in the mid west we easy access to most places around homes. Also I only have about $5K total investment in my old school grinder. She is very profitable at that cost.
If I did a large volume of work I would consider a more modern unit though. In our area lots of home owners take down their own trees so volume isn't that high on the stumping side. If in a larger market area it would be different again.
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