Reddit mentions of Arm & Hammer Super Washing Soda 55 oz.

You can get washing soda cheap! A 3lb+ box goes for about $10 on Amazon, but you can also probably find it in a larger store's laundry aisle. Mix this up with some borax (also cheap) and maybe some grated Ivory soap and you're set on laundry detergent for a very long while.

You can get percarbonate for cheap too! A 6lb tub goes for $5 or so at Walmart.

Not necessarily. For example, Amazon's cheapest Washing Soda is $2.71 a pound while their cheapest pH Increaser is $1.68 a pound. Both are 100% sodium carbonate.

EDIT: Correction, the washing soda is 15% water(PDF), making the pH increaser even better.

Hi! So I was in the same pickle as you, really wanted to do cloth but with the washer/dryer situation I was worried it would end up costing us even more. So I investigating the most effective way to hand wash. I use a mobile hand washer with prefold diapers. The AIOs will not work with my method for several reasons but I don't like AIOs anyways, namely because you have to wash both parts every single time you use them. Prefolds + cover, you can reuse the covers a few times before washing. Plus, prefolds are much cheaper, softer, and I think the sizing lasts longer. You can also fold them many different ways to find the best (read: cleanest) fit because every baby is different!

I have 27 prefolds and 7 covers, I believe. This is just enough so that I don't completely run out of diapers by the time the clean ones finish drying on the rack, if I'm leaving the washing til the last minute (usually like every 1.5 - 2 days, but it's better to wash them every day). It takes 10 minutes of plunging in a 5-gallon bucket and maybe another 5-10 minutes of wringing out with cold water. I find it to be kind of meditative and if you get into the plunging it is a good work out, too.

After I bought the plunger I realized I'd need a better detergent solution, too, because I need roughly a cap's worth of detergent each time I do this, which is at least 5 times/week, plus our regular laundry. This is another reason AIOs won't work. The laundry soap I made contains Borax, which will mess with the elasticity of the diapers (the prefold covers, too, but that's okay because I usually just wash those with a bar of laundry soap, Felsnaptha, soak in cold, and throw them in the dryer during our weekly/ twice weekly wash of clothes). Very very cheap to make, 20 cents/gallon.

Oh yeah, and I just throw the prefold diapers in the washer & dryer with the rest of the laundry whenever we do that, whether or not they're dirty (actually, if they're dirty, I still give them a quick wash/rinse anyway, I don't want them yucking up our clothes). They take up almost no room and it keeps them softer.

Washer
http://www.amazon.com/gp/product/B003SQ7I5S/ref=oh_details_o03_s00_i00?ie=UTF8&psc=1

Diapers:
4 packs of these -
http://www.amazon.com/gp/product/B003AJXY1U/ref=oh_details_o02_s00_i07?ie=UTF8&psc=1
1 of these (super deluxe, was a gift, sooooo soft) -
http://www.amazon.com/BabyKicks-Pack-Prefold-Diaper-Small/dp/B001NAAQPU/ref=sr_1_1?s=baby-products&ie=UTF8&qid=1376071041&sr=1-1&keywords=baby+kicks+diapers
7 of these -
http://www.amazon.com/gp/product/B003AJXY1U/ref=oh_details_o02_s00_i07?ie=UTF8&psc=1
1 pack snappis
http://www.amazon.com/gp/product/B004YWKWJO/ref=oh_details_o00_s00_i00?ie=UTF8&psc=1


Detergent recipe - http://theurbanfarmingguys.com/diy-laundry-soap-20-cents-a-gallon
Products -
http://www.amazon.com/gp/product/B000R4LONQ/ref=oh_details_o02_s00_i01?ie=UTF8&psc=1
http://www.amazon.com/gp/product/B0029XNTEU/ref=oh_details_o02_s00_i00?ie=UTF8&psc=1
http://www.amazon.com/gp/product/B0063KXEIG/ref=oh_details_o01_s00_i01?ie=UTF8&psc=1

• I found the Fels Naptha Laundry Soap at Wal-Mart for 97 cents a bar surprisingly! On Amazon it's more expensive but you might find it other places. According to their website's store locator, places like CVS, ACE Hardware, Harris Teeter, Kroger, Publix, Piggly Wiggly, & others should carry it.
  
  
• To note, the Arm & Hammer Super Washing Soda is not baking soda. It's also in the laundry detergents aisle. I bought it at The Commissary on base here but their store locator indicates Walmart, Costco, Home Depot or Lowe’s should carry it.
  
  
• The 20 Mule Team Borax can be found at many of the same stores as the Fels-Naptha - here's their list of stores. Again I bought it at my local Commissary.
  
  In my opinion the internet is too expensive if you have a store nearby, however, even if you triple the inflated cost (as the Amazon seems to be more than triple for the soap, and the Washing Soda and (holy moly) quadruple for the Borax, the materials are $45.88 for 1 Box of Borax, 3 Bars of Soap, and 3 Boxes of Washing Soda, which make about 18 Batches total, that's 936 loads of laundry which is equal to $0.05 per load, still cheaper than Amazon's All Small and Mighty Free Clear at $0.11 per load.
  
  I know there are cheaper detergents than that out there but that's what we used previously and I know what's in my detergent & have less trash to toss. It might not be worth it at $0.05 per load for some, but if you get the materials at a similar cost as to what I got them ($1 per laundry soap, <$3 each for the Washing Soda & Borax) then it is WAY worth it.
  
  Best of luck!

amazon :)