Count Back?

If two or more players have the same score, you take the best back 9 score. If that's the same, the last 6, and then the last 3. No idea beyond that though!

18th after that.

There is actually no 'Rule' for countback, but that's the 'standard' one - and the default in most Handicap systems. It's part of the Committee's responsobility to define Countback 'rule'.
 
It's back 9 then back 6 then back 3 and then the 18th.

In nett competitions the handicap should be subtracted.

HTH
 
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