Hi Andi,
Some very good budget friendly dry food brands are Dr. Tim’s and Victor. Chewy.com has Dr. Tims. You can get Victor on Amazon. Both brands have large bags 40-44 lbs for $50-65. Plus, they will last you longer because they are high quality and you will feed less of them. To stretch out the canned food, try adding other tasty things to his kibble like eggs, canned fish (sardines or salmon), plain yogurt or kefir, or healthy bits of your leftovers (veggies or meat if not seasoned to heavily.
I hope this helps. I know how expensive it is to feed big dogs. I have a 150lb Great Dane.
