Finally after 15 months of playing Eve I have filled the third slot.
The driver for this is Oliver's recent move into wormhole space.
Being realistic, there is going to come a point where I am podded out and will have an issue getting back, so paying for a months training to up the scan skills and some basic PI and I will have someone that can at least scan the way back in.
Also with a few planets PI it helps pay the fuel costs.
There are now two residents in my POS, both me.