To date I have installed an HBI flat trigger with 3 pound striker spring $55, Gray Guns Super Black Stainless Steel Recoil Rod with reduced load 15b competition spring $40, and Cajun Gun Works tool steel striker $48 or an investment of $143 which when added to the $460 cost of the P-10 brings my total investment to $603. My last upgrade will be tritium sights and I am leaning towards the Cajun Gun Works 018-590 tritium rear sight and the 019-425 tritium front sight for $118.95 Still checking out others though. So far I have installed everything myself which, if you knew my limited gun smithing skills, is major accomplishment for me. Its amazing what you can do by just watching a few YouTube videos. Since I don't have the proper tools, I will have my gunsmith install the tritium sights. I could not be happier with my P-10 now that I have added a few goodies to it. BTW my P-10 was a perfect fit in the custom kydex holster I had made for my Glock 19 so no holster expense for me.