I know, I know with what I wrote in the question I shouldn\'t be surprised. But my situation is slowly working on an inherited POS system and my predecessor apparently wasn\'t
A general purpose way is to coerce the collation to DATABASE_DEFAULT. This removes hardcoding the collation name which could change.
It's also useful for temp table and table variables, and where you may not know the server collation (eg you are a vendor placing your system on the customer's server)
select
sone_field collate DATABASE_DEFAULT
from
table_1
inner join
table_2 on table_1.field collate DATABASE_DEFAULT = table_2.field
where whatever
You can use the collate clause in a query (I can't find my example right now, so my syntax is probably wrong - I hope it points you in the right direction)
select sone_field collate SQL_Latin1_General_CP850_CI_AI
from table_1
inner join table_2
on (table_1.field collate SQL_Latin1_General_CP850_CI_AI = table_2.field)
where whatever