Follow up question - Do I need a 5gal or 10gal cooler?

Original Question: https://www.homebrewtalk.com/f11/do-i-need-5gal-10gal-cooler-123555/

Three follow up questions:
1. I saw a couple of responces that pointed to a 12~13lb grain limit for a 5gal cooler. Can someone point me to a source for this information? Remember that I have never done an AG brew so this may be common sense to some of you.

2. The comment was maid "if you are batch sparging a 5gal cooler would be fine", but.... what if I wanted to fly sparge in the future

a) Would the grain bed depth of a 5gal batch (say 12lbs) in a 10gal cooler be to shallow to be effective?

b) Would there be enough room in a 5gal cooler to fit a sparge arm?

Thanks
Cootr_brn

Like someone else said, get a 10gal now, or kick yourself later if you don't.

I think the main problem I have is that "I AM CHEAP" and if I can get something that will last for a couple of years then I might go that way. Even though I like the idea of the 10gal cooler I want to make sure that I need the 10 gal cooler. I also looked at a bunch of recipes that I would like to try and I have not found any that go above 1.065 in OG. So.... I still have not decided

I'm cheap too. While being cheap, you should think of the long run too. Eventually you will want a 10gal, probably sooner than later. I'd go ahead and get it, instead of buying a 5gal, then buying a 10gal later. Wasting money. Home Depot has them for $40. I'm sure you will want to do a bigger beer soon enough.

You need a 20gal, but those are really hard to find Go for the 10gal, you'll never say it was too big.

See, I told ya this question was hot lately.
https://www.homebrewtalk.com/f11/how-big-your-mash-tun-needs-123585/#post1378917

Thanks BobbyM - that is exactly the information that I was looking for.