About breaking dead limitations

I’m sure this was already picked clean in terms of what can and can’t be done within this type of mode. What I’m curious about is can we do buyable items like HMG implacements, doors, light armored vehicles like the M3A1 (light armor vehicles with open tops so you still have to be careful with exploding engineers) etc. or is it just weapons and the box?

I asked this because you can set a prefix for heavy MGs but it don’t seem to cost anything despite showing a price allowing a player to use it for free. Vehicles seem to do the same.

Doors however, I’m not sure, I think this would be interesting to see if this is possible but I’m not sure how to go about it.

I’ve already seen “modified weapons” like the PPS-42 and others with changed stats within the Nuketown mod but I’m curious to know if this is as far as it can be pushed.

How far can we really push this within mods?