The keys to finding good used equipment in Wisconsin are persistence and patience. There are plenty of good machines out there at reasonable prices. You just have to know where to look. I would suggest visiting some local machine shops and let the owner know you're looking for a particular type of machine. It's a close knit community and they all let each other know when they are either buying or selling machines. The company I worked for had several machine shops in production or rebuild facilities across the country. The shops were always being visited by vendors of some sort or another. Over time you learned from them who was buying and who was selling. You also learned how shops treated their equipment. Other good places to look are local high schools, municipalities, universities, and technical colleges. Machines from these places are generally in like new condition, and go for prices less than a dime on the dollar. Wisconsin has several online sites that cater to the above mentioned entities.
Here are a couple sites:
http://www.maxanet.com/cgi-bin/mncal.cgi?rlust
https://swap.wisc.edu/
http://www.publicsurplus.com/sms/all,wi/browse/home?tm=m
https://madison.craigslist.org/search/tla?query=milling+machine
Over the years I've purchased over a dozen machines. Some from businesses downsizing, upgrading, or changing focus, some from schools and universities upgrading, and others from used equipment dealers. All the machines have been in excellent condition, and none cost nearly $4,000.00. My latest purchase was a Sheldon MW-56P lathe. It was totally rebuilt from the ground up including having the bed and saddle ways reground. It came with several chucks, follow rest, steady rest, 5C collet drawbar system, dog plate, face plate, tool post, and other assorted tooling. It's the first machine I purchased out of state. It came from a shop in the Chicago area that had replaced it with a larger machine. This was the most expensive machine I've ever purchased, and was slightly more than half the price BO mentioned someone was asking for a machine in poor condition.
Another way to keep the cost down is to provide your own transportation. When buying new most manufacturers or dealers will ship to a local freight depot for minimal prices. The big cost is to get it from the depot to the final destination. I have moved machines in my own 5 ton trailer, in the back of a pickup truck, and even rented a drop bed trailer. I was given quotes from $1,800.00 to over $3,000.00 to move my latest machine from the Chicago area to southern Wisconsin. In the end I rented a drop bed trailer like this one for less than $200.00
https://www.sunbeltrentals.com/equi...0150/6ft-x-12ft-lift-bed-tandem-axle-trailer/
It took less than a day to pickup the lathe and get it home and unloaded. I returned the trailer the following day. All in all it was an easy and inexpensive way to transport a heavy and awkward piece of equipment.