Usually jobs like this will require , chas , safe contractor or similar , as has all ready been said at least 500k in the bank and confirmed by your accountants figures for the last 5 years , that’s how most tenders like this work , you will more than likely have to be iso90001 , and have policies in place for sexual, religious, ethnic , and gender non discrimination , unless you are a big company I doubt you will evan qualify to tender , they certainly won’t allow sub contracting . You might not want to hear this but if you want regular well paying commercial work look else ware , this isn’t the type of job to start off with you need many years of large commercial in the private sector before trying to do stuff like this , and I bet they will only want to pay peanuts after you have jumped through all the hoops as well . Don’t waist your time filling out all the paper work that will take hours to revive an email later saying “ sorry but you weren't successful this time but we will keep your details on file “