As per my title, I'm wondering if any of you would design retaining walls without geotech reports? I find often with residential projects, no geotech exists and the client does not want to pay for one. Would you say no to doing the design, or if you would design it, what would you deem as conservative and reasonable assumptions for the design parameters? If you backfill with a granular material and install a weeping tile at the bottom of the wall, can you eliminate any hydrostatic pressure and just assume a saturated soil?