Subject makes tracking difficult?

How do private investigators work when their subject changes their identity, hardly ever go out and if they do they use a rental vehicle under a different name, don鈥檛 answer their telephone at home but use a cell phone instead, and limits their friends? Doesn鈥檛 this make the investigation harder if your subject hides his tracts and specifically his moments and/or location?

No matter how a person tries to use different names, tries to "change" their identity, uses a cell phone, etc., one thing will always track someone. Their money. If you can track credit card and bank account usage, you can follow someone every time.
By the way, parabolic or directional microphones are not useful to private investigators, only law enforcement. Unlike the movies, sitting across the street in a van will only net you one thing, a visit from the local PD when the neighbors or the subject himself calls the Police on you for being a "suspicious person."

Experienced investigators know how to track even the most cautious subjects --- cell phone numbers can be traced, utility bills, once a location is verified they have "amplifiers" (that's not what they're called but you get the idea) that they can drive by the location and point it in the general direction and pick up conversations in the house --- or sit across the street in a van listening to conversations --- this includes telephone conversations (one sided, of course), they can also put a tap on the phone line outside the house to hear both sides of the conversation -- there's a LOT of different ways they track them depending on the specifics of that particular case.

there are ways even the best cant evade....