Order allowing a “private auction” of real estate among the beneficiaries of the estate was an order that determined an interest in real property within the meaning of Pa.R.A.P. 342(a)(6), so that it was appealable as of right and the failure to appeal from the order was a waiver of the right to appeal. The gains realized by on the sales of the properties should have been reported by the estate and not reported as gains on sales by the beneficiaries of the estate, but the method used to determine basis of the properties, by multiplying the assessed value by the common level ratio, was proper. The finding by the Orphans’ Court that mineral rights in the real property were owned by a beneficiary and not the estate was vacated because it was based entirely on judicial notice of a deed without notice to any party or any opportunity to challenge the implications of the deed. Krasinski Estate, 2018 PA Super 130 (5/15/2018) (en banc). aff’g in part, rev’g in part, vacating in part, and remanding, 5 Fid. Rep. 3d 275 (Clearfield Co. O.C. 2015).