Using public copy slots sucks but eventually it gets the job done and FINEG can't come along and destroy the station. A job came out of the factory that contained 20 Invulnerability Field I BPCs with maximum runs, and hey, whadda-ya-know I've got over 300 Hydromagnetic and Quantum Physics datacores to burn. Buy a pack of Twinkies baby, time to do some inventing!
In twenty invention attempts I got 10 successful returns, exactly 50% as expected. I love it when probability behaves. That means the invention cost per run is 311,600 ISK based on current datacore prices. With a build cost of around 1 million ISK per unit and a sale cost over 2 million ISK, I'm looking at a approxiamtely 600,000 ISK profit per unit.
(Note to Anon poster on Onyx post last week: this time I've included datacore costs but not the BPCs costs which amounted to a few thousand ISK for factory time and the BPO cost which has long since been paid for. )
Since I'll build and sell 100 units, the modest profit margin means 60 million ISK profit. Not bad, but I still remember the days when Invul Field IIs sold for over 4 million a pop. Sigh, made a fortune in those first few months of invention.
In other news, I found a container with a whack of old sheild BPCs like X-Large Shield Booster and Large Shield Extender and Sheild Recharger that were all max run from the Kodachi Enterprises days. I decided "what the hell" as I have extra datacores and threw them into the labs as well. Got a couple X-Large Shield Booster IIs and still working on the rest.