One of the lowest priced train sets that come complete with tracks and power functions to motorise the train is the Passenger Train 7930.
Power Functions to motorise the train include an IR speed remote control, IR receiver, battery box and train motor.
These will cost about $55 alone if bought separately. A box of flexible train tracks run another $20. This set retails for $129.99 making the rest of the train and station cost only $55.
Sets like the Horizon Express 10233 are more detailed but retail at the same price. However, they do not come with any power functions or tracks.
So if you want to motorise other LEGO trains, buying the Passenger Train 7938 makes good sense to obtain the power functions and tracks.
You could then sell the train away or keep the parts for other random builds. One idea is to use the red bricks to make a nicer train station instead of just an open platform.
Year Released: 2010
Retail Price: $129.99