Buying physical gold is generally a rip off. Only place I’m aware of getting a halfway reasonable deal is to buy at the Dubai gold souk, need to report >10k to customs.
Everywhere else comes with high fees, transaction costs. Need to insure If you keep in house. I suppose a decent sizes safety deposit box will hold a number of kilos, say 10 or roughly $500k (10×2.2x16x1400)

I’m mostly in ETF like GLD IAU, and GDX and select higher quality miners such as AEM, newmont, etc. All protected by trailing stop orders