Built out of house guttering to a scale equivalent to model railways HO the layout is approx. 4 x 3 ft. Mounted in a wooden frame and provided with a protective see through cover it fits into the car and can go anywhere. it has been an on-going project to build RC boats to suit. Those used at present are commercial products (loa 5" (125mm)) with simple two channel two prop drives - not proportional but with forward and reverse and by operating one or both props plus reverse steering is OK. Battery life limited to 6-8 minutes with similar recharge time. Built largely from scrap and odds and ends the project cost well under £80. The idea is/was to have several units and link them together to make a large layout!