What would be the most stable yet uncomplicated RC adaption of a plastic inject kit not designed for RC?

My vote is for either the Lindberg Diesel Tug or the Lindberg Shrimp Boat. Both are single screw and can utilize a hacked standard servo for main propulsion which is super cheap. Another micro servo for moving the rudder (easily $2.99 more or less on ebay), a 4.8V receiver battery pack and a cheap-o but basic 3 or 4 channel 2.4 GHz HobbyKing radio set (under $30) and you're good to go. Figure on getting some brass rod and tube for fabricating the prop shaft and stuffing tube along with a small piece of brass sheet to carve into a rudder. Also a rudder linkage which can be a fancy proprietary RC item or just a piece of wire (or that brass rod you have for the prop shaft. The most expensive thing is going to be the kits themselves which invariably retail for ridiculous prices sometimes; between $30-$45 but often pop up on that popular auction site with low starting bids.

One of the best conversion articles here (techniques adaptable to the Shrimp Boat as well):

http://www.boatnerd.com/model/tug/

http://www.boatnerd.com/model/tug/others/hyneshowto.htm

If you can find one, the Lindberg 1/32nd scale PT 109 would be a good choice.  Dumas has some easier boat models with vac formed plastic hulls:  USS WHITEHALL (PCE 599); CAROL MORAN; and  U.S. Army ST Tug.

RC Groups has a whole lot of plastic kit conversions: www.rcgroups.com/.../search.php

Felix

Looking at your budget you may struggle. If I was looking round I'd look for one of the Italeri 1/35 boats like the Schnellboot, Vosper or the Pt boat. I've seen them converted, they are a good size and should be very stable

Phil