It had to be powder form, liquid is just a storage nightmare.
It could not be scented, I break out in hives.
It had to be cost saving.
Over time this is the recipe I found. It is from Being Creative's site
Now her version lasted 9 months and cost about $20.00, mine lasted about 24 months (but at the time I was the only one using it).I did tweek the recipe a bit, I suggest you check out the original and try what works for you.
1 4 lb 12 oz box Borax (2.15 kg or 76 oz) found in the detergent isle
1 4 lb box Arm & Hammer Baking Soda (1.81 kg) found in the cooking isle
1 box Arm & Hammer Super Washing Soda 55 oz (3 lb 7 oz) found in the detergent isle
5 bars of Fels-Naptha soap, found in the detergent isle (if you use Zote
bars use 2 bars instead, Zote can be found at Home Depot)
1 huge container of Oxy Clean or store brand Oxy Clean (5 lbs total )
Sam's Club was great for finding huge amounts.
or
You should be able to find all of these items at your grocery store.
I grated the naptha soap, and in a large bucket combined all the other ingredients until completely mixed. I use a 2 tbs scoop.