Sorry this took so long- it was about 5 minutes of formatting that I kept putting off. You can find the spreadsheet here. The bolded numbers are numbers that you can change to play around with. The first page has two areas- the left one is "what are my probabilities on hypotheses A and B given that the house has been shown X times and has received 0 offers", and the right one is "what would be probabilities on A and B be if I show the house X times, receive 0 offers, and then receive one offer?"

The second sheet is "given that I started with a uniform prior over success rates between 0 and 0.1, how many more times do I expect I need to show the house to receive an offer?" while updating on the information that you haven't received an offer yet.