Towing Issues: Signage and tow laws, tow company, signage

Question
This question is regarding towing regulation in Boston, MA
Car was towed from parking spot behind a store by what appeared to be a roaming patrol operation. I'm told nobody called for the tow from the store. Long story short, the layout of the lot is ambiguous, there is a kind of tow away over a couple of spots, but not near where car was parked and no sign at any of the entrances.

Question is, isn't there a requirement for signage? Is any sign within the property sufficient? Besides that, in this jurisdiction, is roaming patrol allowed? Finally is blanket authorization by the property owner allowed so that tow company can decide what to tow by itself? Thanks.

Answer
http://law.onecle.com/massachusetts/266/120D.html

Boston has many many laws regarding towing, but this is one of the easiest to understand...

Signage is always an issue, some people think signs should be in each space, while others think that signs at the entrances work good.
Plus given weather, vandalism, and just plain lack of understanding of the laws for posting signs makes it hard sometimes to be legal or keep signs posted.