Planning to DIY a paver patio in this area. The existing concrete floor is about 9 inches higher than the surrounding soil, and I want the finished pavers to be 3–4 inches below the concrete. Do I need to add fill dirt, or can I just compact 4 inches of gravel and add 1 inch of leveling sand? I’ll be using 16 × 8 × 2-inch concrete paving stones. TIA!

https://imgur.com/a/Au0Kyvw