As everyone probably knows by now, trikes are my thing. Rarity is not necessarily value. Grycner was not a manufacturer (except for the trike modification). They were a distributor (kinda like Cosmo) that slapped their name on another manufacturer's product. In the case of Grycner, they imported Jui Li mopeds from Taiwan back when they were not so good. The moped used for this trike is a Jui Li product, identical to a Clinton. The "Sachs" motor was actually built under license and is a Taiwan clone not quite up to the same standard. So it is not something that needs to be preserved without mods. Go ahead and make it your own.