The founders will sign the company contract in the office of the notary

They should take an appointment.

The cost of establishing the company should be payed at this moment. As from the moment of signature the notary is responsible for the payment of the registration tax. Especially in real estate transactions when this tax is 10% of the value, the notary can't allow that the costs will be payed later. As the notary holds money from several thrid persons, he can't be allowed to give credit.