>A custom asked me to spec memory and hardware for building a VM that will host SQL Server 2008 (for my VFP/ASP.NET application). I don't know how to define the load that the application will have (actually there will be 5 applications and 5 databases). But in general terms what is the average amount (or min-max) of RAM I should ask for the server? Any other hardware specifics you think I should recommend?

One thing to consider is the amount of tasks running in memory and how much they will take. Then, you need to reserve some memory for the running of applications, caching and stuff like that. The good answer is as much as you can put. :)

VM setup tends to follow a trend where the box will be less powerful, but together will provide a better performance. I prefer to continue to use high performance boxes on the entire VM setup.