this topic has been brought up many times.
buy something you can ride for a season, drop a time or two and not cry like a bitch, sell the bike the following season for what you paid for it (someone elses is always looking for a "first bike" to drop and not care). once youve decided riding is for you buy the bike you want!
my first bike cost me $400 (89 suzuki gs500), put $300 in it (rear tire, chain, battery, etc), dropped it 3 times and shrugged each time, sold it at the end of the season for $850.
since then ive learned what not to do and havent dropped either the gsxr600 i had or my shadow :knocks wood:
go test drive that cbr, if it rides straight and starts easy and the parts that stated to be new/rebuilt really are tell him you have a grand cash and see what happens
it appears to have been dropped before the fairing is damaged on the one side, have the owner take off the fairings and inspect everything!
more details on the 954