What are BTVG confirmations? BTVG confirmations originate from the Property Developer Contract Act and confirm the completion of a construction phase. If the agreed price is paid according to an instalment plan when purchasing a property, the respective instalment is only due after completion of the construction phases specified in §10(2) of the Property Development Contract Act. The basic idea is to create an appropriate distribution of risk between the property developer and the buyer. Payments by the buyer are made in line with the progress of construction and the associated increase in value of the property. Each further payment is therefore always linked to the actual completion of the previous construction phase. The following construction phases represent the milestones of a construction project at which instalments are due: -Start of construction -Completion of the shell and roof -Completion of the shell installations -Completion of the façade and windows, including glazing -after completion of occupancy or in the event of agreed early handover of the actual object of the contract -Completion of the entire facility -the remainder after the expiry of three years from the handover of the actual subject matter of the contract, unless the property developer has secured any warranty claims and claims for damages through a guarantee or insurance (§ 4 Para. 4) The construction progress shows little flexibility and must always be completed in its entirety. The windows, for example, cannot be invoiced without a completed façade. However, it is possible to bring forward an entire construction phase. In order to determine the completion of these construction phases, the trustee can call in a civil engineer responsible for building construction, for example an architect, a generally sworn and court-certified expert for the construction industry or a domestic regional authority active in the context of the promotion of the project.