For future reference chaps, there is an answer to this in the legal term (UK) "Repairers Lien" It basically means that you can collect the repaired item when you pay for it in cash, and not untill!
I had a sign in my workshop which said:
" All repairs must be paid for cash on collection. No credit will be entered into. Uncollected repairs will be kept for 3 months, then may be sold to ofset costs. Storage will be charged after 1 week."
I actually won a Jaguar XJ6 with this, so I know it works (in the UK anyway, other areas must check their local laws.)
Phil