What to make UPS for a router / access point?

Question

Uninterruptable power source

I'm in the process of installing WiFi base stations. It is necessary to ensure their smooth operation.
The price is far from the last.
1) At the input we have several power sources: PSU, solar panel, possibly a mini-wind generator.
Task: It is
necessary to organize automatic selection / simultaneous use of a power source.
Access points operate on 24V voltage.
Solar panels are 12V each.
I was thinking of using a multi-input charge controller, but there are none at normal prices. Although there is one with one panel entrance for only 5 euros.
Maybe someone from the outside will suggest a solution?