BikeCad is a terrific program and certainly if I was using it for business I wouldn't think twice about purchasing BikeCad Pro. I just want to design a bike for myself. In order to proportion everything properly I need the rider display which is not available in the free version. My geometry is unusual so trying to work by measurements alone is too time consuming and prone to error. My suggestion is to implement a means to purchase BikeCad Pro on a per design basis. One way could be to disable the generation of any type of output. Encrypt the saved design which could only be opened on the host computer. Then the designer could upload the encrypted file to your website and purchase the desired output be it a photo or an unencrypted file to be sent out for fabrication. As an added incentive you could offer users an unrestricted licence once they have purchased output equal to the purchase price of the software. I’m not willing to pay the price of BikeCad Pro for a one time use. The above is something I definitely would be willing to pay for – and I’m probably not alone.