Implementation about EPPM R8.3

 Implementation about EPPM R8.3 

My doubt is this:

I have 10 user who want to use EPPM R8.3 with:

-P6 Web
-TeamMember.
-WebServices.
-Professional Client R8.3

All in SP1.

But on sizing doc I found this:
A small deployment:
App server: 4 gb ram
Database server: 8 gb ram
P6 Services: 8 gb ram.

It is needed to have P6 Services in another server or can be on App server?????

Why so much resources if I am going to have only 10 user working but not at the same time on Primavera R8.3

Thanks,