It's better than buying new... if you don't see many of these come up for sale in your area, yes, it's a good deal if everything is working.
Like the rest said, 6 footers are nice, as is rear discharge.
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Copy of the Ad so people in the future can see it:
Very nice 60 inch Sitrex finish mower model, number SM 150. I purchased this mower new in 2006 and it has had low use since purchase It is in excellent condition. Price is $750.00. Call (540) xxx-xxxx. Here are the specifications:
3 point Hitch CATEGORY 1; Blade Rpm r.p.m. 2632; Cutting Height 1'' to 4''; Cutting Width 60''; Hp Required 15 to 30; Number Of Blades 3; PTO r.p.m. 540; Standard Wheels 210 x 80; Weight 435 Lbs