Trying to do something like this:
select 'Setup for Car ' + CAST(varchar(50), @CarID) + ' for user ' + CAST(varchar(5), @UserID)
doesn't work, not sure what the syntax would be then for T-SQL. I've hunted around, have not found it yet.
You can user either of these:
select 'Setup for Car ' + Convert(varchar(50), @CarID) + ' for user ' + Convert(varchar(5), @UserID)
OR
select 'Setup for Car ' + CAST(@CarID as varchar(50)) + ' for user ' + CAST(@UserID as varchar(5))
You are using CAST wrong. It should be
CAST(@Variable AS WhatYouAreCastingTo)
Remember, MSDN is your friend :)