While others have provided good info/links for you to review/study, I see a detail which might need 'special consideration' ... 'technical support in school'. Is the 'school' a K12 entity where students/teachers will be using your Moodle in a F-2-F classroom ... 40 classrooms, 40 Teachers, +total number of students 1000+?
And then, of course, what those students would be doing .... all taking a quiz on Friday of every week?
A 32 Gig all in one box (web service + database) might handle it but then again if quizzes aren't broken apart into pages of questions, server might struggle. Difference is usage - asynchronous (like a higher ed entity - no F-2-F) vs synchronous (a k12 entity IN a F-2-F).
2 cent thought.
'spirit of sharing', Ken