SUPRDAVE(a)aol.com wrote: Cordata took over Corona and I *think* they were located somewhere around Westlake Village, California. Both the Corona and Cordata machines that I have are all MS-DOS machines and I don't recall their ever running CP/M. When Cordata ceased operations, the service and support was taken over by a company in Los Angeles (don't recall the name, but I could probably find it if it was needed.) As with everything, the value is what someone is willing to pay. If the machine has all the documentation, I *might* go as high as $20 but that would only be because of the docs. BTW, I seem to recall that the monitor was specific to the machine so make sure the monitor comes with the machine. Without docs, I *might* be willing to take it off someones hands but only if it were in excellent condition and working. The Corona PC400 was my first MS-DOS machine. The Northstar Advantage was an integrated machine that has the terminal, processor, etc. all in one case; kind of a nice machine. It ran CP/M and came out after the Horizon. I mainly used the Horizon so don't know the details of the Advantage. The two Advantages I have were given to me and included all the documentation. With the usual "it is worth what someone will pay", the prices I have seen on similar equipment at swap meets, etc. run around $10 or so. It is worth a bit more with docs. As far as "worth getting", that depends on what type of collection you want and how much space you are willing to devote to the collection.