Albertsons is the least coupon friendly of all of my grocery stores. They do NOT accept competitors' coupons and do NOT double coupons.
Ralphs doubles coupons up to $1.00 but does not accept competitors coupons.
You have a coupon for 50cents off an item. Ralphs will double the coupon so that you receive $1.00 off the item. If the item is on sale for $1.00 you will receive the item for free. HOWEVER, be aware that some coupons say "customer pays sales tax" at the bottom. This means that even if you received those 12 tubes of toothpaste for free, you will be paying tax on the standard or sale price.
You have a coupon for 75 cents off an item. Ralphs will add value to the coupon so that it equals $1.00. That is, Ralphs will give you 25 more cents off of that item so that you receive a total of $1.00 off of that item.
Vons will double coupons that are at or below 50 cents. They will not accept competitors coupons.
**NOTE** Catalina Coupons
You may have noticed the last time you went to the grocery store that you received coupons with your purchase. These coupons typically come out of a machine called a Catalina Machine. These machines can offer both manufacturer and store coupons. As a result, you can take manufacturer coupons you receive at Vons and use them at Ralphs so long as they say "Manufacturer Coupon".
Additionally, you can find Catalina coupons online at CouponNetwork.