What PoE number should I check on a 24-port access switch?
The watt budget on that exact PID, not a family brochure. WS-C3850-24P-L lists 435W. S5024PV5-EI-HPWR lists PoE+/UPoE but no watt figure.
Does a data-only 24-port switch belong in that comparison?
No. C9300-24T-A and S5735-S24T4X are Non-PoE.
What if the uplinks are only 1G?
Say so. S5024PV5-EI-HPWR lists 2 × 1G SFP. A 3850 uses a network module, which may be 1G or 10G.