Same story at my cousin’s store in Inwood, the cheap DIY cameras gave us nothing usable. What fixed it was a professional video surveillance installation https://www.4wires.com/ from 4Wires, they have been doing cameras for over twenty years and know retail layouts. They mapped the blind spots first, then put cameras over each aisle end, the register, the entrance at face height, and the stockroom door. Recording runs continuously, and pulling a clip for the police takes a few minutes from the phone. They work with Hikvision and Dahua gear. Honestly, it cost more than I expected, but the losses dropped noticeably within a couple of months. Tip: ask them to put one camera at the exit at face level, that is the shot police actually use. How many aisles do you have?