The 144 converter pen has two well-known weak points. Its cap is a slip cap and is prone to cracks at the cap lip; in time, too, it no longer closes reliably. At the front by the nib sits a gold-plated ring which can break down under constant contact with ink. The cap lip, wear on the cap rings and the condition of that ring should therefore all be checked. The official successor is the 145, the Hommage à Frédéric Chopin, which matches the 164 ballpoint well in size and is regarded as more robust.
The price of old examples depends almost entirely on condition, and beyond that on rare nib widths and on whether all the parts are original. The 144s of the 1950s were frequently on offer in 2006 and ranged from well under 100 to about 120 euros. The version with a flat cap top from around 1961 counts as a transitional model and turns up less often; whether that makes it worth more was a point on which collectors did not agree.