Very easy to use, I trimmed my driveway up in Chicago with one I rented from Home Depot. Cost $40 IIRC, be sure to get the diamond blade, I think it was $20 extra ($60 total). I basically plugged it in and used it like a circular saw - cut right through the concrete like a hot knife through butter.

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08 W251 R350
97 W210 E320
91 W124 300E
86 W126 560SEL
85 W126 380SE Silver
85 W126 380SE Cranberry
79 W123 250
78 W123 280E
75 W114 280