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Currently apartment sitting for my BF. He's a fairly clean person but for the past three days house flies have been all over the place. I have taken precautionary measures by pouring bleach down the sinks/bath tub and but putting out ACV (apple cider vinegar) traps out as well. The flies seem to be dying down but there are definitely still some flying around. The apartment has been scrubbed clean and I still can't seem to find where they are coming from. There are a few by the garbage can but the garbage has been taken out and has a lock lid so I doubt that's where they are coming from. I also know they're not coming from the sinks because I block the drains when I am not using them. Any help and advice is appreciated!