How much cash?...
No one here has cracked how to make an enviroment or to edit them. We can edit ships but thats as far as we've gone. The game wasnt really designed for modifications and we have had little success at editing it. It also uses some obscure code engine.
This thread in the cookie box may interest you and give some background knowledge:http://forum.shipsim.com/index.php/topic,15515.msg403449.html#msg403449
If you still are interested I can teach myself to make models and my going rate is $100 a hour and Ill need at least 30 hours of doing it and there will be other costs involved