Legal Question in Wills and Trusts in North Carolina

You ask a bunch of questions and you don't provide much information.

What assets are in your mother's estate? Is there enough other stuff (besides the land) to pay off any debts of the estate? If not, then the real property will have to be sold, used to pay the debts and the balance given to you and the two other children. Does the will require your sister to get approval from the court? Does it say anything about her duties to get the land surveyed before the share is given to each beneficiary?

Surveying the land could be for lots of reasons. Maybe there is just one big tract which is to be left to you and the others and it will have to be subdivided. Pricing is done for various reasons too. Land may have to be valued for tax purposes through an appraisal. It does not mean that it is necessarily going to be put on the market. Further, the will might direct that the land be given in equal shares to the beneficiaries and if each beneficiary is to get a parcel, then some kind of appraisal is going to need done for each subdivided parcel.

Why is the executor taking a 15% share of the estate?

I could speculate all day, but the only way to know for sure is to get a copy of the court file and take it to a probate attorney in the county/state where your mother's estate is located. Pay the attorney to review the will and inventory and tell you whether the will allows your sister to take 15% and subdivide and sell the property.