How should I best handle a rapidly growing database?

Question

I have a database that I need to maintain.

Sadly, the setup and use of that database I can't change, much (thanks to some internal politics).

It's running on SQL Server 2008r2.

Its only been live for 5 days and has grown from 20GB to upwards of 120GB in that time. (essentially most of the data gets deleted and then imported, but like I say I can't control that side of things)

I would love to run nightly jobs to shrink the database and reorganise the indexes, but I know that's a long way from best practices and could lead to more problems than I've already got!

QUESTIONS

• What's the best way to handle a database that's rapidly increasing in size?
• Should I be looking at moving the file group around to keep the physical size on disk down?
• Is there any way to stop the server running out of space within a month?