The fact that they are similarly priced deserves investigation. Is the house trading space and control for condition, access or energy performance? Is the condo priced for a particularly desirable building or location? Finding the reason for the price overlap could reveal the real compromise.
Is the 255 m² confirmed internal usable area, measured on the same basis as the comparables? Two bedrooms within that area is unusual enough that I would inspect the area schedule carefully. Storage, common areas or other non-equivalent space could distort the €/m² calculation.
Is PLN 3,674,000 a firm ceiling or a currency-conversion figure? Its precision may cause confusion when people assess budget flexibility. It would also help to give an availability window: vacant now, completion within a few months, or no fixed deadline. Those two clarifications should make any...