A reasonable offer is the one recent comparable sales justify. Days on market rarely tells you what to pay. Homes sit for all kinds of reasons that have nothing to do with a motivated seller: the listing launched in a slow season, the home is genuinely unique or very high-end, or the whole neighborhood simply turns over slowly. So compare against the typical days on market for that specific area. If homes there usually go in about three weeks and this one has sat six months, that points to overpricing or a defect worth investigating. If listings in that neighborhood normally take three to six months anyway, a long sit is unremarkable, and a one-of-a-kind or luxury property can sit a year without being a red flag. Before you assume leverage, have your agent talk to the listing agent and dig for the real story: why the home has sat, why the sellers are moving, what actually matters to them. A divorce, a trust sale split among heirs, or a seller already in contract on their next home each create very different room to negotiate. And don't treat a vacant house as automatic motivation; plenty of vacant homes never respond to a reasonable offer at all. Anchor your number in the comps, understand the seller's position, and be ready to walk if the deal doesn't pencil.