Pennsyvania Law on posting private property for intended use any other use the car will be towed at car owner's expense.

There are no magic words in my state. All such signage needs to impart the message intended and be clear in intent. Check to see if there are similar signs in the area that have the message you seem to think would be best for your circumstance.

If it were me, I would contact the Quakertown code enforcement officer and zoning administrator so that your sign(s) comply with all applicable sign ordinances. The wording is up to you.

Good luck to you.

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