Ok, i have a case maxi sneaker, vermeer lm 25, lm11 and a ditch witch 410. I've done a lot of work on all of them. The first thing i would do is make sure that the big ticket items are in good working order.( engine, pumps, pto, boring attachment, hydraulic cylinders, etc...) Just keep in mind you can get a good used trencher for around $3,000 to $3,500. So don't waste your time on a machine with a bad pump or some other part that will cost you more than the machine will ever be worth. For parts, try napa you will be surprised at what they have + its a great place to have hydraulic lines made. As a last resort you can go to the dealer but it will cost you.
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