First off we were "bothered" by missionaries about once a month, mostly at mealtimes. My usual response to them was a polite "no thanks" and closed the dooris it "dishonest" to talk nicely to a missionary
After being confronted by a pair of dishonest missionary's i cured any and all interaction with them from that point
The story.
A knock at the door, a well dressed man and woman holding a small pile of magazines. Yes we were eating lunch. "We would like to give you this magazine about your heart" fly cover identified it as an NHS magazine with NHS logo in NHS colours, with 3 heart related leaders on the front, continued on page x..
I took the mag and off they went, we finish lunch. I opened the mag. Inside front (and rear) covers were blank, the fly cover was loose and inside was a Watchtower.
I ordered two signs "Unsolicited callers will be reported to the police". Had one stuck on the gate and one in the porch window.
Next time there was a missionary knock I'd open the door, point to the sign and take out my phone, "Hang on, I'm just calling the police"
Was never troubled with them since.
Been here in France for over 8 years and never seen a missionary.