Three new builds have been deployed by CCP on the test server, bringing most of the missing graphics and icons. Quick look at POS structures’ BPOs shows that the prices will stay roughly the same (supply/demand might influence a bit), at least when compared to each other. A good example can be Small Ship Assembly Array (90 mil isk NPC price) compared to <racial> Control Tower Small (100 mil isk NPC price). The amount of planetary advanced materials needed is 4 materials of each type to build both. The same does not apply to large towers which now cost 3 times the price of small tower, but according to the new BPOs it will become 4 times more expensive.
Feel free to have a look at some screenies: