Flat Sharing Experience

I'm thinking of finding a flatmate to share a two-bedroom flat, as the rent in HK is getting increasingly difficult to afford. But I haven't been living with a flatmate since college days, which was many years ago, and I couldn't remember how it worked. I can think of many daily issues which must be sorted out, like keeping the flat tidy, guests visiting rules, sharing of groceries/utilities bills, making sure rent is paid promptly etc... Anyone has experience sharing a flat with a stranger, and anything good or bad or to learn about the experience?