1) Claude: 180 euro / month, Codex: 100 USD / month

2) no

3) Defaults: claude and codex

4) I've built my own custom system including web UI which helps me manage agents powered by claude and codex in both headless mode and running through an automated pipeline including bug reproduction, dev, code review, qa, etc... It's proving very useful, and keeps getting better as models improve. Opus 5.5 is phenomenal.

5) I tried OpenClaw but it didn't stick for me