The most used prop

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Here's the Top 25 props that appear in the most OFFICIAL maps
Where official maps means they are listed in tf/cfg/mapcycle_default.txt

Spoiler

44 props_2fort/miningcrate002
42 props_2fort/miningcrate001
42 props_2fort/oildrum
41 props_farm/vent001
40 props_farm/pallet001
39 props_lights/light_fluorescent_basement
39 props_gameplay/sign_gameplay01
38 props_gameplay/security_fence256
38 props_lights/light_cone_farm_32
38 props_farm/conduit02
37 props_spytech/terminal_chair
36 props_mining/conduit_outdoor512
36 props_gameplay/uniform_locker
35 props_trainyard/handrail128
34 props_2fort/groundlight001
34 props_lights/light_cone_farm
34 props_spytech/intercom
34 props_spytech/vent
34 props_2fort/tire001
32 props_mining/junctionbox03
32 props_mining/ceiling_pipe_128_thick
32 props_farm/wood_pile
32 props_gameplay/security_fence128
32 props_spytech/wall_clock
32 props_farm/conduit_pipe01

Edit: I should also mention this list is currently static_props only

 

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A per map table of non-static props has been compiled!
This list counts everytime a prop appears in the entity lump in an offical map
Strangely I had to make allowances for maps that contain props which don't have models (I'm looking at you cp_junction)

All static_props are counted once, which is why security_fence256 is one of the 'least used' props on tc_hydro
I'm having a little trouble getting decoding the static props at the moment but I'll update the list when it's working

 

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put a somewhat formatted table of static_props & enitity_props up on google docs:
get it here

and the script if anyone wants to try some other maps OR get the raw data: