Do large purchases for customers affect your annual turnover? Subject to VAT

Hey,

If you have to make a purchase of 45,000 euros for a customer and you would charge 5,000 for your wages. Then your income states 50,000, but your actual profit is only 5,000. Does this affect your vAT type? I would like to remain vAT exempt, but i don’t know how to approach/record this larger project so that I can do so. Do you have the answer to this?

Thanks in advance!