Transportation to Port of Houston from Bush

Anyone know a reasonable method of transportation to get two of us from Bush to Kemah, and then Kemah to the Port of Houston?

We stayed at the Kemah Boardwalk Inn last month. We took a taxi. The fare was $115 with tip. I had looked into various shuttles and limos and for a party of 3, but didn't find anything that would be cheaper than a regular taxi cab.

If you stay at the Boardwalk Inn, print the directions from their website. You cannot count on the taxi driver having any idea where this place is. Also, the entrance to the hotel is actually on the 2nd floor of the parking garage, which was not at all obvious in the dark.

Taxi from Kemah to the Houston port was about $20.