Shock from workshop!
Just got the quote from metal workshop about motor-gearbox adapter plate and shaft coupler production. They've quoted the sum equivalent to around $700-800 for materials and works for this not so complicated product! I really hate when someone is trying to rip me off just because they see that the project is not cheap and quality is needed. I'll skip their offer. Anyway I'll have to look for another workshop or other option to produce the adapter plate and coupler.