Try saying out loud, You are our hope. You really don’t want it to sound like Your are are hope, now, do you?
Often, the ‘our’ in sentences is unaccented. And many times, we glide over and mumble unaccented vowels until everything sounds like ‘uh’ (or ‘uh-r’). So, yes, regionally, some people make the ‘our’ sound like ‘are’ in casual conversation.
But when the ‘our’ is accented, it is usually pronounced with the long ‘hour’ sound.
Beatles: %Hour house, is a very, very fine house…%
When you do public presentations, readings, dramas, or songs, always pronounce it clearly as ‘hour.’ In coaching someone doing a public reading, I penciled in an ‘h’ in front of every ‘our’ so the speaker wouldn’t say ‘are.’