Final answer:
In the preparation for a real estate hearing, the power to execute and sign subpoenas lies with the judge overseeing the case.
Step-by-step explanation:
In the preparation of a real estate hearing, the power to execute and sign subpoenas that require the attendance and testimony of any witness and the handover of any paper or books is given to the judge overseeing the case. The judge has the authority to issue subpoenas to compel witnesses to appear in court and provide testimony or produce evidence relevant to the case. This power is derived from the Sixth Amendment of the United States Constitution, which guarantees the right to confront and cross-examine witnesses.