Title company backed out of the same-day close 48 hours before settlement
First one I got all the way to a settlement date and it died on the closer's desk.
Numbers: contract with the seller at 112k, end buyer signed at 131k. Small 3/1 in a working class pocket, seller was moving out of state and wanted a date certain. My purchase contract had resale and title-taking language in it, so the seller and their agent both knew I was going to turn around and sell it. Nobody was surprised by that part.
What killed it: I called the title company early, asked "do you do double closings," and a person at the front desk said yes. Two days before settlement the escrow officer called and said their underwriter won't insure two deeds on the same file in the same day unless the first leg is funded with the buyer's own money, and my plan was to use the end buyer's funds for both legs. So they wanted me to bring 112k. I didn't have 112k or a funder lined up, because I had convinced myself the dry close was the normal way this happens.
I had eight business hours to find another closer in a market I don't know well. Didn't happen. Inspection period had already run, so my 2,500 earnest money went to the seller, plus about 600 in inspection and courier fees. Seller relisted, and I'm fairly sure my end buyer bought it direct six weeks later at 124k.
What I'd do differently: get the escrow officer, in writing, to confirm they do dual closings, name which transactional funders they've closed with, and say whether they'll allow the second buyer's funds to cover the first leg. All of that before my inspection period ends, not after.