The let out clauses
For you, the purchaser, the suspensive clauses protect the deposit you gave to the notaire or agent as part of your agreement to purchase the property.
The most usual is a clause stating that your agreement to purchase is subject to you obtaining mortgage finance.
Other clauses can be inserted, such as the vendor having to carry out necessary repairs or subject to the dimensions of the property corresponding to what is detailed in the Compromis, and this is where expert legal advice is useful in the negotiation of these clauses.
On the day of signing the Compromis de vente you will be required to pay your deposit to the notaire or the agent. No compromis can be signed without the deposit being cleared funds in the notaires/agents bank.
Once you have signed the Compromis de vente - you have got a set date by when you should complete on the purchase. You are given a 10 day cooling off period (10 days in which to change your mind) from the date of the signature.
Even though you may have a clause suspensive in the Compromis stating your agreement to buy is subject to mortgage finance, if you do not make reasonable efforts to obtain mortgage finance in time, then you could lose your deposit.
Also if you intend to substitute yourself with a company ie an SCI and the SCI does not obtain its mortgage then the name of the buyers who signed the contract will lose your deposit.