As AWL has pointed out, the weather when you plan to come back is the biggest gotcha.
It is all too easy to be sucked into a trip by a lovely forecast on the departure only to be trapped by miserable weather when people need to get back to work, school, etc. I was once driving back to Toronto from Thunder Bay being chased by a warm front. I stopped by the Sault ste. Marie airport for some 100 octane for the R5 and came upon the a/c I had done my IR in. The pilot had taken his gf up for the Agawa Canyon train ride only to return to said wf and had to take the bus home and make expensive arrangements to retireve the a/c
Others with less sense have made expensive holes in the ground.
Bad timing -- I would have let him drive my car back while taking gf and a/c back had I known his schedule
