Theoretically you could setup the domain so it would direct to different parking services, however, this could violate the TOS of some parking services and this would not be possible with all services. Overall the best and most simple option is to chose one specific parking service. You can try out different ones to see which one would work for best a certain domain. Unless this is a high traffic domain with high revenue keywords you could easily spend too much time testing out different services in comparison to the gained revenue.