The security service of many large companies is categorically against agreements not supported by a seal. This is the internal policy of the company and hardly anyone will change it for the sake of one transaction. It is easier for potential partners to find a supplier (buyer) with a seal than to take unjustified risks.
In addition, for many customers and partners, the presence of IP printing is a sign of solidity and reliability. Organizations and private individuals are more willing to deal with stamped transactions.
For ordinary buyers or customers, in the absence of a cash receipt, only a document containing a seal is official. It is often almost impossible to prove the opposite to them.
Making the simplest in terms of design and printing mechanism will be inexpensive. For the basics, I recommend using stamp online . Prices increase depending on the type of equipment and the time of manufacture. So, for urgency you usually have to pay extra. There are no special requirements for the company's stamps.