I'm really not to good at balancing cost / profit :(

[Malaras]

For my new products I added. I'd like to keep them on par with other things in the game.

Any tips?

Also will the AI use modded products that are added?

[Dav3]

You can see what variables other products are using in the Product_Types.xml and use the same for your products if you don't feel experienced enough to experiment for yourself.
Just look here if you dont understand some parts http://www.capitalismlab.com/advanced-m ... ducts.html
AI will use the products you create too so no worries about that.
Hope I could help, feel free to ask if you have more questions.