BTW No SOLICITING is not the same as No TRESPASSING; different laws.
The WTS has shot down No Soliciting laws in the past and recently in the courts, including on the US Supreme Court level.
Whereas, the WTS has backed away from "no trespassing" issues and have told JWs that it is their own personal decision if they disregard these lawfully posted signs, that the individual JW will be responsible for all court costs and fines, and that the WTS will not necessarily supply a lawyer.
I have seen several cases of this locally and the lawyer the WTS suggested was a brother with no experience in that kind of law; the brother charged lost and had to pay the fine, a fairly substantial one, $300 plus costs.
Since the directive from the WTS to the congregations regarding "no trespassing," the JWs here skip over those houses.
I would not pursue enforcing "no soliciting" requests, just check the laws in your area regarding posting no trespassing signs and keep them clearly posted. Follow the reporting laws in your area if JWs disregard the sign.