I dont know about you - I cannot abide flies in any shape from or size. They buzz they dont buzz f the silent ones are the worse. Creeping up on you - silently sitting on your knee twitching there feet together in a quite ghastly beat. YES I think I have made a point I DON'T LIKE FLIES OF ANY SIZE.
What can we do - squish -squash- splat chase them around the room with a broom a tennis racquet a rolled up newspaper a fly swatter. Squirt them poison then I read about a way of keeping them out and I am so demented with them I am about to try it out.
Take a clear polythene sandwich bag
Fill with clear water about half way
pop two or three five p pieces in
tie up the bag Hang at doorway or window where flies come in!
Thats it end of problem - eh - yes they won't cross the thresh hold why well what they see is a giant lies eye warning them off.
Sounds reasonable I shall try it today you try it too lets see if it works!
Good luck - flicks fly of key board - xgins