How much is Week and Seed and how much it covers.

Buy what you need and can afford

Also, depends on the product. Weed and Feed may not be the best bet for you. But on average, about $35 for a 20/25 lb bag.

Depending on the size of the bags you buy. It is written on the bag so you will know before you buy

Depends on the square footage of the area you plan on planning

Weed and feed? And it basically covers where you use it