1. Yes for hcg, no for oils. Im saying to pin oil and hcg separately
2. Best to use insulin pins with fixed needle, as no product is lost in these
3. 250uis is same in every pin. If you use 2ml in 5000ui, 0.1ml will be 250ui. So its the 10 mark on the insulin pin.
4. Yes, 2 IM pins for oils, 2 subq pins for hcg. Subq pins are very easy to do...
5. Its rubber, it will close it self up. Impossible to reuse same hole.