kenwood help KR8840 reciever

I have some old audio equip I'd like to sell on ebay, but cannot find anything on it,
one item is a kenwood kr8840 reciever, the other is a sony tc730 reel to reel, a akai gxc570d, if anyone knows about this stuff or where to find info, I'll buy you a beer!
Dave

If the Kenwood is the KR-8840 QUAD, it is 40 watts per channel and was made between 1974 and 1978. It retailed for 800 dollars.
Your Akai cass player, GXC-570D was made between 1976 and 1978, it retailed for 900 dollars.
I could not find info on the Sony, I am using a Orion Blue Book back from 1991. You may want to find someone with a newer copy.