The property exterior was (eventually) redesigned so that lookiloos wouldn't easily find or recognize it. The house number was even changed! I don't think the tile walkway was replaced or resurfaced right away, unless there were damaged areas that had to be repaired. It really comes down to the condition of the property. The concrete walkways outside were washed down. They were not otherwise damaged though they may have been fixed/replaced as years went by, based on the city's maintenance schedule.
There is no law against bettering a dwelling or easement or land, after a scene has been released by LE, as long as the necessary paperwork has been obtained, depending on the jurisdiction and rules of the property location. In the case of PTL, it does not appear to be a legal issue, just one that some Interweb dwellers are having a tough time accepting, for some reason.