Compact 5V power supply for embedding in a socket: How to choose?

Question

Do it yourself

    For a DIY project, I choose a compact power supply 220V -> 5V. It is supposed to be built into the socket for 24/365 operation (yes, partly based on this post ). The idea of ​​gutting usb charging is tempting and easily accessible, but I would like to find a separate board, so that in case of successful implementation it would be possible to order 10-20 of them at once. A search on aliexpress showed a large number of different options with a considerable range of prices, while for me, as an electronics engineer, it’s not entirely clear how they differ. For example, this power supply has 2 transformers, and this one has one, it is not clear what this affects.
    In the first place, side by side with compactness, is reliability. Accordingly, the question(s): How to choose? [What to pay attention to? What is the minimum price a reliable scheme can have? What components should be looked for on the diagram?] Links to proven options are welcome.

Answer 1

One has a current strength of 1A, the second has 0.3A. One has a power of 5 watts, the other has 1.5 watts. Your relay uses 0.083A, so it shouldn't matter if you don't decide to immediately connect 100 relays to the first and 30 to the second

Answer 2

There are also such
ru.aliexpress.com/item/New-Travel-Convenient-EU-Pl... ,searchweb201644_0,searchweb201560_3