If more than one owner is involved, or the property is held by a trust, company, or estate, ask the title company and your attorney to confirm who can sign from the deed and the relevant estate or court records. Put the written offer and written terms in front of you before you commit.
Property taxes, mortgage payoff, recorded claims, Wisconsin transfer-fee and title items, and other settlement costs can affect what you keep. The county's tax records and the title company can help you check the figures for the property; the calculator is an estimate, not the final settlement amount.
For a tenant-occupied house, bring the lease, access limits, and any notices into the conversation. If a lender, court, or sheriff date is driving the sale, use the actual notice and get advice about that date from the right professional. A buyer inquiry does not change a deadline.