If you are being offered the chance to fly in the RHS on single pilot ops and get to fly the empty non commercial sectors, or positioning flights, (assuming they really are non commercial sectors) then go for it, but if you are expected to work in the office 5 days a week whilst waiting for a flight you should be paid for the work you do in the office.
If they will not pay you for office work they are taking the ****
Also be very careful that the legs you fly really are non revenue positioning flights.unless you are correctly opc, fire and smoke, first aid trained etc