Worth keeping old 1KW laser just for marking?

I have a late 90's Mazak (Panasonic/Mitsubishi) 1KW CO2 laser in good shape with a lifetime of consumables and spares. The product line I bought it for is finally going into production, but I'm not going to cut my parts on my laser because it's cheaper to pay the shop across the street with millions invested in brand new machines to laser my stuff.

Older lasers don't go for much so I'm trying to come up with a sound use for it. I was thinking if I could use it to mark all my parts that would be the perfect use for it. I could pull the slats and make dedicated fixtures for different part families. I make a wild range of stuff from the size of a thumbnail to the size of a mini fridge.

Dumb question time-

1) Is the machine I have effective for laser marking my stuff? Everything I make is either Type 3 ano'd 6061, black oxide steel or silver zinc electroplated.

2) If it is, do I need any assist gas for marking? Do I need a dust collector? I don't really want to invest in a 10+ HP metalworking dust collector if I can avoid it.

3) There are materials that I have to apply to the parts to facilitate the marking correct? Any vendor recommendations? Do I need to wash the parts after marking?

4) Is there software geared specifically toward laser marking?

We have an old 1500 watt Mazak STX 36 from the the mid 90's and a new 2015 STX 3015. I'll answer your questions based on our experiences with the older machine.

1) We have used the older machine for laser marking material. We typically have used it on stainless steel & nickel alloys.
2) We use Oxygen for the assist gas. We have a dust collector but never use it.
3) We just clean the sheets prior to laser cutting or run them through wet timesaver belt finishing machine prior to laser cutting / marking. Marking with Oxygen will leave a dirty appearance so i would recommend cleaning.
4) We use our nesting software that the program is developed in. The text is put on the 2D flat pattern of the part we are cutting and the operator will adjust cut conditions for the text at the controller to get the laser marking to show up adequately.

Hope this helps.
Derrick