"tmtresh" wrote:
Now, this is my plan of action
1. Rototill the existing lawn
2. Cover it up (~1000 ft^2) with tarp to kill the weeds (and whatever
else was growing with weeds) - ~2 weeks?
3. Put in some new top soil
4. Apply weed killer chemicals
5. Re-sod
6. Water
7. Water more

If you are going to put topsoil on top, there is no need to rototill.
Save yourself some work, and just cover the grass/weeds up with a tarp.
Also, the topsoil shouldn't have any weed seeds,

Good luck finding sterilized top soil, except maybe in bags.

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