The base price shown is for the lowest cost VDO sensor in the list of those available above. The additional cost depending on the type of sensor chosen is shown on this list and is in addition to the base price.
The VDO Pressure Sensors shown above have a single output with a 0-5 BAR range, suitable for 5 Bar VDO gauges. The resistance output is ~10-180 Ohms.
"Earth return" means that the sensor is earthed via its thread / engine block (there is no separate insulated connection for earth).
(Insulated Earth Return sensors or sensors with a low pressure warning contact are listed on the product page separately.)