1. The mini fridge: It seems there is some consensus around the viability of the Sanyo 4912. This will fit in my closet nicely. Is 2 cornies the maximum capacity or can 3 be squeezed in?
No clue. Try it and see what happens.
2. Does the CO2 canister need to be stored upright or can it be stored on its side?
I would keep it upright.
3. I am used to bottle conditioning beer and plan to do natural carbonation in the keg. What are the potential pitfalls beyond the possibility of a bit of sediment in the first pint or so?
Zero issue. Just lack of patience lol
4. My local bar has left over corny kegs from an experiment they did with cocktails on tap and has asked me to take them. Is there any reason I should not do so?
You should not take them. Give them my address and I'll dispose of them properly
5. What is the best method of sealing around the holes I will need to drill in the fridge?
Rubber grommets just make sure you don't hit anything important.
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