The single most costly is overpricing at listing. Per Colorado Association of Realtors, 57% of Denver metro homes that sold in 2025 had at least one price reduction before going under contract. A price reduction signals something is wrong — even when nothing is — and typically nets you less than correct pricing from day one. The first two weeks drive the most traffic; don’t waste them on an aspirational number.
Other common mistakes: skipping professional photography (listings with pro photos sell 32% faster per NAR data), neglecting pre-listing repairs that will come up in inspection and give buyers negotiating leverage anyway, being inflexible on showing schedules (every missed showing is a potential offer you never received), and not preparing for the appraisal gap — in a flat market, appraisals sometimes come in below contract price.