I will forever be BAFFLED by ANY fear of elders. They have exactly the power you give them......how can a 'fader' be worried about spying elders?
Most states have anti-stalking laws....simply mention it and they will scatter like cockroaches.
Gone are the days of spying, sitting out front of homes in cars, etc. They can be arrested!
Don't answer the phone. If they leave a threatening message; keep it......contact an attorney and have a letter drafted on stationary threatening legal action......CC the Watchtower Bible & Tract Society on the letter.
Seriously......stop fearing these jokers.........99% of elders can't find where there arse is!!!
By the way....you would be amazed at what happens when you disfellowship THEM..........shun them!