Outboard questions please help

Some of the ads I am looking at for a new used boat say the compression on the eng.
The only problem I have with that is that I have no idea what it should be. A mechanic I am not. Does any one know what the compression should be on Suzuki or Mercury.

One of the eng. is a Merc 225 Optimax, and another has twin Merc. 115's, and another is a Suzuki 225 that says it is at 150 on each piston. The last one is a 2005 Merc. 200 hp at over 120 psi on each
HELP
 
Top