If anybody is interested. I am very happy to have my DTV visa through Warsaw embassy. Very fast process - working week of waiting
In my case following document were sufficient:
- scan of passport
- photo
- proof of funds from my savings account translated to English (official statement from bank with a stamp) plus its translation
- scan of my ID card as proof of residence
- a statement from my employer/ main business partner about my role/position as a B2B contractor plus explicit statement that I am allowed to work remotely from outside of Poland indefinitely and that he acknowledges I will be working from Thailand
- I was NOT required to present my contract
Everything was surprisingly smooth and got my visa after 10 calendar days.