Disklavier

Hello everyone, new member here.  I do not yet have a Disklavier but 
have been looking for the last 4-6 months.  I am in the market for a 
used piano and have been doing some research.  I will take a few days 
reading (most likely) every post for the past year or so before I 
start asking detailed questions.  I know how tough it can be with the 
same questions being asked over and over again when a little digging 
will find the answers.  I do have one quick question, is there a 
Disklavier for Dummies or Disklavier FAQ's, etc that I can read 
somewhere.  I looked here in the files and there was not one.  
Specifically what I am looking is info on the various models, year 
they came out and can they be upgraded to (lets say) a Mark IV 
system.  Thanks again for my membership (Jim-Maryland)