No
The garage can hold the vehicle as a lien for payment they have carried on that car.
The garage cannot hold a different or unrelated car for securing payment for unpaid work.
Bailiffs cannot take control of a debtor's car while it on garage premises. The law says bailiff may only take control of a debtor's goods,[1] where the debtor usually lives or carries on a trade or business,[2] or any highway[3] in England and Wales.[4]
[1] Paragraph 10 of Schedule 12 of the Tribunals, Courts and Enforcement Act 2007
[2] Paragraph 14(6) of Schedule 12 of the Tribunals Courts and Enforcement Act 2007
[3] Paragraph 13(1)(b) of Schedule 12 of the Tribunals, Courts and Enforcement Act 2007
[4] Paragraph 11(1)(a) of Schedule 12 of the Tribunals, Courts and Enforcement Act 2007
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