(a) The proper county for commencement of a proceeding pursuant to this division is either of the following:
(1) In the case of a living trust, the county where the principal place of administration of the trust is located.
(2) In the case of a testamentary trust, either the county where the decedent’s estate is administered or where the principal place of administration of the trust is located.
(b) If a living trust has no trustee, the proper county for commencement of a proceeding for appointing a trustee is the county where the trust property, or some portion of the trust property, is located.
(c) Except as otherwise provided in subdivisions (a) and (b), the proper county for commencement of a proceeding pursuant to this division is determined by the rules applicable to civil actions generally.