This is what I'd keep in my car if I had matte paint or a wrap to safely spot clean gently without damaging the matte surface, if say a bird got me.  

The Autosotlz Quick Detailer and Clay Lube has great lubrication and adds no shine, its normally used by professional detailers when claying before a ceramic coating as they don't want anything that leaves waxes or ceramics behind, its also a great quick detail and spot cleaner.  Its gentle, safe, and the best option for spot cleaning if something happens and you can't wash immediately.

The Pegasus cloth is super plush thick and soft, and the lowest risk for scratching.  If you have bag grime you could step up to the rockcar roadie cloth which grabs better but this is your lowest risk and super soft. I'd go with this and repeat if you need to.  let the quick detailer soak a while first so the grime is softened and loosened.  use flat folded into 4 (don't bunch), and swap to a clean side as you go.

Tip:  The Autostolz products come with a double seal and a separate trigger, reusing this cap for storage reduces leak risk if you can't keep the bottle stored upright.

New kit more info to come.