We have owned several hobies including our current adventure island sailing trimarans. But to the point, we had 2 adventures that we fitted with the sidekick ama kit( a hobie option) which is essentially two inflatable amas. These are side stabilizers that reduce the need for a ballasted keel. I have not looked recently but these were available for their inflatables. It would still be good to use the blades on the pedals as a sort of centerboard. For limited space this is a good option but be aware that for an experienced sailor there is a big difference. That is why we now tow a trailer with our adventure islands. I do not know current costs but hobies are expensive, but worth the cost IMHO. After further research it appears that the amas were not designed to fit on their inflatables. What I have seen must have been semi-custom. Still, the ama kit is inflatable and can be easily stored.