They cost memory. No money though.
No, it's not legal to sell Minecraft maps/mods.
Not completely, many people make Minecraft maps for fun and for personal use without charging. They may ask for donations for the hard work they put into their maps, but many of the maps would not require a fee to use.
no
No. Demos for games do not cost money.
It does cost money. but you can download it illegally
Minecraft forge is a free program.
No, it does not cost anything.
No they don't.
no
No
Well, you need the game 'minecraft' which does cost money. Pixelmon is just a mod for the game 'Minecraft'.