Multi-loan simulator: build a property financing plan

Build your plan in Monetra's multi-loan simulator, then use this guide to check the balance of its funding lines and interpret both charts.

A French property financing plan may combine a standard mortgage, a state-supported PTZ, an employer loan or another negotiated facility. Looking at each one separately hides the household's actual monthly commitment. Monetra merges their schedules and exposes the initial payment, peak payment, interest, insurance and remaining principal.

Project cost is calculated from the property price, agency-fee percentage and acquisition-fee percentage. Every loan then has its own principal, term, nominal rate, insurance rate, insurance basis and start-month offset.

Monetra generates an amortization schedule for each line, shifts it when required and adds payments that occur in the same month. The “standard,” “PTZ,” “employer” and “custom” types mainly label the line. Selecting PTZ sets its nominal rate to zero in the interface, but the application does not determine eligibility or the legally available amount.

Balance the financing plan first

Before studying payments, verify that down payment plus total borrowed equals project cost. The “financing gap” is this difference, and Monetra flags an absolute mismatch of at least one euro.

A negative result means some cost has no funding source. A positive result may indicate duplicate principal or fees treated as financed even though they will be paid in cash. Correcting the mismatch ensures that competing scenarios cover the same purchase.

Understand the start offset

Before a loan's chosen start month, its payment is zero while its principal remains in the aggregate outstanding balance. Amortization begins when that month arrives. The model does not accrue bridging interest or capitalize charges during the wait. It therefore represents a simple repayment offset that reveals a payment step, not every contractual form of deferred credit.

Complete the project card first, then add loans one at a time. Give each line a descriptive name because the label is reused in the monthly chart and loan-level summary.

• Principal: enter only the amount allocated to that loan, never the down payment.
• Term: use that line's own amortization period.
• Nominal rate: use zero only for a genuinely interest-free line; do not enter APR here.
• Insurance: select initial or remaining principal according to the scenario being quoted.
• Start offset: express the repayment start as months after the global beginning.
• Type: use it for readability, then check the product's real conditions separately.

The interface permits long technical ranges, but they do not imply that a lender will offer that structure. France's official Service-Public PTZ guidance explains that PTZ is a complementary loan subject to conditions and a lender decision.

Assume a €200,000 property, 6% agency fees, 8% acquisition fees and a €40,000 down payment. Total project cost is €228,000, leaving €188,000 to borrow.

The financing has two lines:

• a €160,000 main loan over 20 years at 3.40%, with insurance at 0.15% of initial principal;
• a €28,000 PTZ over 15 years, insured at 0.15%, whose repayment starts in month 61.

Loans plus down payment cover the project exactly, so the financing gap is zero. During the first five years, aggregate payment is about €940 per month. When PTZ repayment starts, it rises to roughly €1,099, also the plan's peak payment. Estimated total financing cost is approximately €66,166, comprising around €60,736 of interest and €5,430 of insurance.

The monthly chart reveals the important point immediately: an average over twenty years would hide a payment increase of nearly €159 in month 61. A household budget needs to withstand the peak, not merely the opening payment.

The initial monthly payment adds all lines active in month one. The maximum monthly payment scans the full plan for its highest aggregate amount. They are equal only when all loans start together and their payment profiles do not create later peaks.

Use the monthly chart to locate delayed starts, loan endings and overlap periods. The annual chart compares remaining balance with cumulative payments. Finally, the per-loan summary reveals which line generates the most interest or insurance.

Total paid equals borrowed principal plus estimated interest and insurance. It excludes the down payment because that cash is not repaid to a lender. To understand the full acquisition outlay, consider project cost and any expenses not included in the model alongside the borrowing totals.

Create at least three variants: the proposed plan, a plan without subsidized funding, and a plan with a less favorable start date. Recheck the financing gap and peak payment each time.

Stress the main-loan rate too. A small rate move on the largest line may matter more than an interest-free rate on a small facility. Compare insurance bases using otherwise identical inputs. If only one mortgage is needed, the mortgage loan simulator guide is more direct. To add rental income and expenses after financing, continue with the LMNP profitability guide.

The simulator does not check the income limits, areas, household conditions, shares, regulated delays or eligibility rules of PTZ, employer lending or local support. It also excludes lender-designed smoothing, bridging interest, guarantees, application fees, early-repayment charges and future payment modulation.

Use it to build and compare a timeline, then have every facility, schedule, APR and condition confirmed by the organizations providing the loans. A structure that balances in the model may still be unavailable contractually or may produce a different payment profile in the formal offer.