For those of you with business networking experience -

I'm in the middle of overhauling a small campus network and putting in a new wireless network.

I have about a 250m run to an AP in another building. I've currently have two cheap switches in between that do nothing but boost the power and move the packets along. Of course, between the two switches, the two UPS's they are plugged into, and the AP, I have five points of possible failure that could take the network down.

Are there any best practices to eliminate some of these possible failure points, or any specific equipment you recommend? The AP at the end is a Ubiquiti UniFi which uses a non-standard POE spec, so it has a midstream power injector which is yet another possible point of failure. Is there any standard convention to differentiate regular ethernet cables from ones with POE, like a particular color cable?

EDIT: I should mention that fiber optic isn't an option unless it can be done fairly reasonably by yours truly. I'm doing this on a smallish budget as a volunteer for a church.