The Guests Dropdown will not show if you use Object rentals.

This is enabled from Theme Options – Booking Configuration – Guest Selector Settings

• Select Object Rental
• Select Show the Guest dropdown in Submission Form -> NO
• Once the Object Rental is enabled, all per night labels in the theme will become per day.

You will see the booking form without Guest.

Hide from contact owner form

This is done with css

/*remove guest from owner contact form*/
.modal-body #booking_guest_no {
display: none;
}

Help for custom css.