Size
Entry interfaces are the one- and two-input boxes most home studios start on, like the Scarlett Solo and 2i2, MOTU M2, PreSonus AudioBox USB 96 and Studio 24c. All of them run on USB bus power, so one cable does the job and there's no power supply to lose. Gain is the spec to compare. The Studio 24c publishes 50 dB, the 3rd Gen Scarletts 56 dB, the M2 and AudioBox USB 96 60 dB, and the 2i2 4th Gen 69 dB. A quiet dynamic mic will use most of it. Check the generation too, because it decides drivers and features.
10 models we cover.
Focusrite
USB$55–$80 typical ask
8 on eBay
Focusrite
USB$70–$110 typical ask
63 on eBay
Focusrite
USB$95–$180 typical ask
106 on eBay
Focusrite
USB$70–$130 typical ask
24 on eBay
Focusrite
USB$95–$160 typical ask
45 on eBay

Focusrite
USB$110–$180 typical ask
95 on eBay
Focusrite
USB$190–$290 typical ask
108 on eBay

MOTU
USB$190–$370 typical ask
33 on eBay
PreSonus
USB$50–$75 typical ask
194 on eBay

PreSonus
USB$90–$180 typical ask
19 on eBay