I have a chance to purchase a "new" Kohler 17KW standby generator. "New" means it has never been installed and is still bolted to the pallet. But I suspect it is 10 years old. The engine is full of clean oil. The enclosure is in excellent condition. There's no evidence of mice or other rodents living in it or chewing wires/hoses.
The owner bought it but never had it installed. It is sitting on a porch behind the house.
It is 520 lbs and I'd have to move it around the house to load it.
Question 1: From what I can gather on the Internet, it is at least 10 years old. Should I be concerned?
Question 2: He asked me to make an offer. What should I offer? I've looked at similar used items on eBay but I'm inclined to offer less since I'm not sure if it actually works.