The Fork In The Road

There are two distinct routes as to which way the project may go.
1. Design and build a tricycle.
2. Design and build a tricycle conversion kit.
The past week I have been leaning towards the conversion kit as being more viable as a business idea.
A tricycle is a tricycle - you buy it, you ride and you may decide you don't like it (I know, that's really unlikely!), and as a customer you may feel that you've tied up a lot of money that you would rather have spent on something else.
The conversion kit would need to be detachable. It could be made as a permanent attachment but I think it would defeat the purpose. You buy it, you ride it - and if you don't like it - you can take it off and get your bicycle back.
It should cost a lot less than a purpose built tricycle.
I think these are major plus points. The negatives are -
Not all bikes are the same size.
They're not he same colour.
Should the conversion kit be aimed at a self fit or a factory fit?
I know I've gone on about the cost, but again - it's a major factor.
More drawings and scribbling required....