Adding Bars or Modify Mutiple Attributes during play

I am working on a vehicle combat game, but there are multiple places to track damage: each side of the vehicle, engine, driver, etc. How can myself and players track damage for each of the sections and see when it is taken out, reduced to 0?

If you create character sheets for the vehicles and link Tokens to it, you can add custom attributes that you can reference in macros.(EngineHP, DriverHP, WeaponMountHP, Armor, etc) Perhaps then write a macro like a military Status report? Vehicle Status Report: Port Armor: @{Vehicle1|Armor} Engine Status: @{Vehicle1|EngineHP} Linking tokens to character sheets will also let your players use their own macros (maybe you'd provide them?) so they can query the status themselves. /w me @(target|Token_Name} Status Report: @(target|EngineHP} .. etc If you keep it under three attributes, you could also link Attributes to the three Token bars so they sync and can be made visible to players.

Great, but how would I for example deduce or increase an attribute during play using the chat?

You cannot without using the API.

you wouldn't do it from chat (only API can programmaticly adjust values). You or your players would open their sheets and change the values there. I think if you link the attribute from their sheets to their token's 3 bars, adjusting the bars will also adjust the sheet, but there's no way to have a macro do that.