Claviettas are almost universally in need of repair to make them air tight, and it’s a tricky business.
If you’re visiting the U.S. and don’t have good Amazon access where you are, I suggest ordering for delivery from Amazon to your relatives. It is easier to play a smaller melodica. Among inexpensive models, I’m partial to the Suzuki STUDY-32 for its sound. Currently it’s just under $40 at Amazon (usually it’s cheaper). However, the Yamaha P-25F Pianica is a very high quality melodica, vastly superior, at $55. It only has 25 keys, but it is comparable in construction quality and sound to the more expensive 32 and 37 key Yamahas. I have a large melodica collection, and I play the P-25 as much as anything.
Others will disagree!