General 'European basketball' questions

[LameCode]

Back story: I'm working on a basketball simulation that includes international basketball leagues. The 'on-court' stuff is no problem, but the off-the-court/business/front office side of things is a bit of a mystery to someone versed solely in the NBA/American pro system in general. Any guidance would be greatly appreciated - and I also appreciate the fact that there are a ton of European leagues in a ton of European countries and things are going to be slightly different everywhere - I'm talking more general here:

1) Youth systems: It seems that European clubs follow the football youth squad/under-17s model. Would this be typical in most European leagues?

2) Attendance: In the big leagues - ACB for example - would sell-outs be a given? Or would the lower rung teams be playing in half-empty arenas? In the relegation/B-leagues, is attendance comparable or in general would it take a hit? How about mid-to-lower tier European leagues, do they struggle to fill seats? Again this is very general and I'm sure differs greatly country-to-country, though I would imagine Euroleague/cup would all be packed houses.

3) Salaries: Probably the #1 item as far as variance between leagues, but what would salaries be like for your average player on a squad like Real Madrid? Versus say, your typical French ProB team? It seems very, very difficult to find salary information online for European teams.

We're early in the planning for this phase right now so I'm sure more items will pop up, but again, any info would be greatly appreciated.