It would depend on the amounts applied and whether you need the phosphorus or not (we'll assume you haven't fed for a while and do need the nitrogen).

Figure 2 pounds of starter per thousand square feet and around 8 or so pounds of Milorganite per thousand square feet sums to a goodly amount of both nitrogen and phosphorus for the new seed. Assuming, again, that you need the P. Many soils actually don't.

Thanks for the advice! . that's about what i figured. I was going to do 3 pounds of starter per 1000 but its likely a good idea to scale it back slightly to be safe. I never tested my soil. I usually feed twice a year so its not in "terrible" shape. My lawn just has always been kinda thin since we moved in a few years ago. and i got killed by crabgrass this year.