PS1.7 Currency format custom (In 1.7 version you cant custom $ via Backoffice)Check the follows files to check where put the changes.public_html / translations / cldr #PS17

main--fr-CA--numbers

Check this for sign decimals:
before:
"symbols-numberSystem-latn":{"decimal":",",.........
after:
"symbols-numberSystem-latn":{"decimal":".",.........

Check this for price format:
"standard":"#,##0.00\u00a0\u00a4"....

 also change "grow up" string ":
before: "group":"\u00a0"
after: "group":","

ONLY CHANGE THE LAST STANDARD string.
After:
For normal $ format :
"standard":"\u00a4#,##0.00\u00a0"
for Euro € format :
"standard":"\u00a4\u00a0#,##0.00"
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For the symbol position, open the Translations>cldr>main-en-US-numbers, fins this code "standard":"#,##0.00u00a0u00a4", and change to "standard":"u00a4u00a0#,##0.00"

the u00a4 is the symbol and u00a0 is a space.