A minor point, but when I bought my R8500 new from a dealer in March 2016, Icom advised the manufacture date was September 2015. I did read elsewhere that manufacture ceased somewhere in 2014/2015.
Dealing with deceased estates can be difficult, because usually the family won't be familiar with what they are looking at or for, so cables, power supplies manuals etc. can be a problem.
Before proceeding, if not already get pix of the unit from all sides including the serial number. They at least will give you an indication of the external physical condition of the unit. And yes, exercise caution re the deal.
I had a similar situation buying an IC-R9000 from a family interstate. The original carton was long gone, so I posted them a large heavy duty type with Styrofoam panels and bubble wrap. Being a heavy and delicate unit, at least I was satisfied it would be packed well, rather than in a much smaller carton with crushed newspaper ....