Cooldude, as 3dartisan suggested you can pay for model activation with the money you received from the customer.
3dartisan, your models are well designed and high quality. We get a lot of sales through our internal search. What you could try is to eliminate irrelevant keywords from tags set, so it would list only the most important words. It should bring your models higher in the results page (we are working on improving our search algorithm).
Also you could experiment by lowering the prices with discount function. Other designers lowered the price to the level that net royalties match the royalties they get at Turbosquid. The final price for customers becomes much more appealing, what in turn helped them to considerably increase their sales.
Let us know if you have any more comments or questions!
