You're missing a close bracket.

Should be
CAST (D.Duty_Rate as decimal(22,8))

And is the server default to compress...

You cannot have both sites writeable. SQL's HA features do not scale out writes. There's peer-to-peer replication, but then you really need to localise writes (and at the table level,...

They're separate settings, they do different things and, tbh, when I'm doing audits and I find DBs with both enabled I flag that as a potential problem.

Is the backup compressed?

You can put the tables with the file in specific filegroups and move the files in those filegroups to a different drive, or set limits on file sizes.
Growth of...

You can't do cross-DB referential integrity, so just have to hope the app is written correctly (or use triggers, but they have problems too)

Why is this being done?...

Start by asking the 'security' person where they get these ideas from.

Does every application in your environment use individual logins to the DB for each different person using...

It's not a 'best practice', and finding justification will be rather hard, as people seldom write articles on 'this non-existent security practice is not a good idea'

See my...

The first problem is, the 4th row by what? Tables have no defined order, so saying the 4th row in the table is a meaningless statement.

You're probably better...

That makes sense.

Yes, to implement the partitioning, you need to rebuild the heap/clustered index, as well as any nonclustered indexes you want partition-aligned, onto the partition scheme.
Splitting...