looking for a small handheld television for use in a camper.

I am modifying a van to a camper and do not want to put an antenna on the
roof.
So I am looking for a - not too expensive- handheld tv set that I could use
in the cabin (or outisde - during summer).
I have seen many of these small units in tax free shops at the aiports.
But which would be "good value for money" and do the job as good as
possible.
thanks for any reaction