Most of my experience involves residential so I'm not sure how to handle this situation:

SPECIFICS: Customer has requested a load calculation for his restaurant. He is renting out two adjacent areas in the same building for his restaurant. Both areas have 200 AMP Meters and 200 AMP Panels. One has a 60 AMP sub Panel and the other has a 100 AMP Sub Panel.

When I checked the panel here is what I fould:

AREA 1:
The 60 AMP Load center/Sub Panel (Square D, QO)had 24 Spaces. Is it permissable to install a 60AMP Subpanel with 24 spaces?

AREA 2:
The 100 AMP Load center/Sub Panel (Square D, QO)had 8 Spaces. I'm just wondering if whoever installed these got the load centeres mixed up.

Any comments would be greatly appreciated.

Strictly speaking, there is no connection between the number of circuits and the "size" of the panel.

Do your calculations...square footage, known loads, etc. Compare this to the size of the breaker; do you need more? If so, run new feeders and replace with a larger breaker
Another approach is to turn everything on, and see how many amps are drawn.

There are two major problems with store-front remodels. The first is the mapping and identification of all circuits. Panel directories tend to be inaccurate after a few tenants.
The other major problem is having circuits cross between different spaces. These circuits tend to continue to "cross over" long after the spaces are re-divided. It is in everybody's interest that this situation be avoided.