I'm about ready to start setting up a SQL data warehouse for some SQL Server Analysis Services. The data that I am going to slice and dice lives in an off site database that I don't control, so my idea is to set up regular jobs that go out and pick up new entries and insert them in to my own version of the table.
I am wondering if there are any good tools out there to help plan database space requirements. After only 5 months the table that I am interested in has already got almost 4.5 Million records and by this time next year I estimate that we could be generating 3-4 million records a month.
I guess what I'm looking for is something that I can feed the table definition in to, and then tell me how much disk space a billion rows would take.
Thanks.
 Edit
Well, using Excel I came up with a theoretical 1098 bytes per record using the worst case scenario that a varchar(1000) was used in every single record to the max.
At 4 million records per month that's 48 million records a year and a worst case need of 50 gigs of disk space per year. Dropping that to a varchar(255) gives me not quite 16 gigs per year, and varchar(50) gives me ~6.5 gigs per year.
Anybody out there a better DBA than I am and let me know if I'm way off base or not?
 Edit #2
As requested here is the table definition:
Type Size int 4 int 4 int 4 datetime 8 Decimal(19,5) 9 int 4 int 4 varchar(1000) 1000 int 4 int 4 smalldatetime 4 int 4 int 4 int 4 int 4 decimal(9,2) 5 smallint 2 datetime 8 decimal(18,2) 9 bit 1 int 4 int 4  Grand total of 1098 bytes if all fields are used to the max.