Just out of interest. And if it is a revision that can be easily expanded to 1 MB chip RAM onboard, I might decide to open it.
IIRC, all of the A500 versions sold in North America can remap the trap door A501 from SLOW memory to CHIP ram, for a total of 1Meg of CHIP. The case must be opened to do this.
The MegaChip product (2 Megs of CHIP with a special Agnus on board) could be added to all of these. Again, the case must be opened.
There is a hack on Aminet to modify (rev 5 and 6?) motherboards to get 2 Megs of CHIP. You replace the Agnus and memory chips. I did this 15 years ago.

The A501 is retained only for the clock.
The A500+, primarily sold in Europe, was the only 500 that came with 1 Meg of CHIP standard, expandable to 2 Megs of CHIP with a different trap door memory expansion.
Practically speaking, after remappting the trap door for 1 MB of CHIP memory, the next biggest bang and cost effective expansion is FAST ram. This also speeds CPU operations. After remapping and adding some FAST, I can't remember ever running out of CHIP memory.
Sorry for starting this... 
It's a good discussion. I was referring to the sarcasm of some of the replies.
Try NOT to advertise owning more than 1 or 2 Amigas, regardless of how they jumped into your possession.

There are a few here who are irrationally jealous of others they label as "hoarders".