Physical evidence is perhaps handled with a greater regard, but from what I understand, background info gathered during surveillance isn't always intended for use in court and often really only serves to further the investigation itself. Usually a stakeout is gathering enough probable cause to effectively justify requesting search warrants, which is when the "real" investigation kicks off.

My shared connection to the Realtor dope I wrote about originally is someone I'm quite close to, and through them I've learned some pretty alarming realities of law enforcement.

It seems like the higher up the chain you look, the more indifference or incompetence you find.

Nope. Usually all the court needs is his attestation that he always had sole custody of the evidence