Our intention is to Dry Camp as much as possible and it's important to me to figure out my usage so I can accordingly determine by battery and re-charge needs.

This is based on my camping style and my needs. If wish to have anything added please ask. I also ask that you look at these numbers for they are assumed or from research so far. I will have 'real' numbers once we start up next spring.

Oh ya, I have built a spreadsheet on this which I'll be happy to share once the numbers are close enough to work well. All my numbers are DC amps

Here I go:

First my needs and numbers:

Water Pump 5.5amps 1hr a day 5.5amps

Frig 2amps Run on propane )have heard as low as .5amps)

Water Heater .5amps 2hrs a day 1amp Numbers run .4-.67ah

Heater 6.7amps 1hrs a day 6.7amps Propane, think high, but fan use..

Power Slide 8amps minutes .8amp

Lighting 4amps 2hrs a day 8amps Set high purposely

Fan 1.5amps 2hrs a day 3amps Also set high for an average

Coffee Maker 13amps 7min .8amps I'm lazy and like my coffee maker

Laptop/cell 2.5amps once a day 2.5amps Probably charged from the truck anyway

Hair Drier 83amps 7min 2.6amps Every other day

Phantom Power 10% of above Unknowns

This puts me at <36amps a day. That's workable and here's why.

Battery 2-6v 210ah batteries drawn to 50% Giving 105ah use.

Solar my 130w panel giving on average 40amps daily (sun days)

Recovery by Solar 114% of daily use.

I have just <3 days of autonomy potential before I have to get serious about re-charging. 

That works!

Now, what do I have wrong or forgot?

6v batts will always have greater Ah. Think about the size of each and what the cells inside are. Also the 6v batts are meant purely for deep use. 50% draw on 6v as to only 70% draw on 12v. 

If your only going to use them occasionally, the 12v batts are cheaper to replace when you kill them. Which happens quickly when not used.

Personally, and only my use and research, I find 12v batts have that good old 'cranking' listing which means the Deep cycle is a reserve. The 6v batts are not 'cranking' listed and are only meant for long slow draws.

There also ways to push the 6v batts into a better Ah when charged in a particular manner.

Did you make a mistake? I doubt it.. 

Could you have done better? Depends on how you plan to use them..

Cost wise balances out if you can buy 6v at a good dollar. Saw some Interstate 6's on sale for $20 (the pair) more than my 1 type 27.. 3 times the Ah with the 6's!

$20 more, ya no brainer for me!

It's all in the use.. IMHO

It would be more useful if you instead measured the power usage in watts or watt-hours, because that is what is actually being used; watts, not amps.

For example. 1 amp at 12 volts is 12 watts. 1 amp at 120 volts is 120 watts. Huge difference. Watts are what matters.

I posted on your thread for daily or duty cycle numbers.

Also what are your daily numbers totaling? You are using very close to the same items as I will be.