My all-time favorite under $50 ukulele is the Kmise Soprano Ukulele. I have purchased 8 of them over the years to give to new players.
My absolute favorite sub $50 ukulele is the Kmise Soprano Mahagony Ukulele available on Amazon. It has great sustain as well as very good playability and intonation from the Factory. It comes as a bundle with everything you need to get started like gig bag, tuner and spare set of strings. I have probably bought at least 7 of them just to loan put to new players. It has a very jangly tone and just plain fun to play. I don't have any high end Ukuleles yet but have owned and played just about every sub $200 ukulele on Amazon so I could definitely owned a high end Ukulele by now. I am currently in the process of correcting that mistake by selling alot of them off but I will definitely be keeping at least a few of the Kmise Soprano Mahagony Ukuleles because I know they are great little ukuleles for the money.
Kmise Soprano Ukulele on Amazon is a sub $50 Ukulele I will give high recommendations too. I have now bought about 6 of them for students. It is laminate Mahagony which is to be expected at that price but each one I have gotten has had very good sustain, Intonation and no sharp frets. It has been the only sub $50 Ukulele worth a darn that I have bought that didn't have sharp frets.