Title question any Wisconsin guys here?

I'm looking at a camper that's for sale there.
I went and checked it out a couple of hours ago.
Wife and I are debating whether to or not to go for it.
Story is it's at a storage unit yard. Nobody has paid storage on it in at least 3 years and they're wanting to sell.
The problem is with a title. Being that i am gonna be bringing it back to IL (the most anal retentive state there is, regarding being able to register something that needs a title, without one)
The rental yard owner has started the process of getting a mechanic lien or whatever it is, to get title so he can legally sell it.
It's got a plate on it, expired in 2016.
That's probably the biggest stumbling block to us going for it.
How easy is Wisconsin to deal with, on this sort of thing? We talked about me leaving a deposit
And then paying the rest when he gets the title but I haven't done it yet. Is this easy there or is it a list cause?