Managing LMNP, SCI, and SAS simultaneously: the accounting setup that prevents madness

The multi-structure syndrome

There's an increasingly common investor profile in France: one that combines personal rental investment (LMNP), property holding through a corporate SCI, and freelance activity through a SAS or SARL. It's a tax-optimized structure, recommended by many wealth management advisors.

What these advisors rarely mention is the operational complexity that follows.

Three legal structures mean three completely separate accounting systems, three different tax regimes, three sets of declarations, and three sets of documents to produce. LMNP falls under BIC with form 2031. An SCI subject to corporate tax requires form 2065, accrual accounting, and quarterly VAT. A SAS needs annual financial statements, corporate tax returns, and monthly VAT.

Managing all of this coherently is a first-order organizational challenge.

Three approaches and their limits

The single-tool approach

Some platforms like QuickBooks theoretically allow managing multiple entities. In practice, this means creating three separate "companies" in the software, each with its own configuration. Cost quickly reaches €50-100/month, and the tool remains suboptimal for LMNP, whose French specificities aren't natively supported.

The multi-tool approach

This is the most common scenario: Rentila for LMNP (€10/month), a dedicated accountant for the SCI (€200/month), Pennylane for the SAS (€25/month). Total: €235/month, or over €2,800/year. Not counting the friction of switching between three interfaces, three entry logics, and three export formats.

The absence of an overview is the most critical flaw. No single dashboard shows overall portfolio performance. To get a consolidated view, you must export data from each tool and manually recompile — an exercise nobody does regularly.

The full-accountant approach

Entrusting everything to an accounting firm eliminates technical complexity, but at a steep price: €300-500/month, or €3,600-6,000/year. And even then, the owner remains responsible for providing clean data — which brings us back to the original problem.

The fourth way: intelligent specialization

The most efficient approach identifies what can be automated and what requires human expertise, then optimizes each component separately.

LMNP and SAS activities are perfect automation candidates: transactions are relatively simple, documents recurring (receipts, invoices, quotes), and tax exports well-defined.

The SCI, on the other hand, justifies maintaining an accountant: accrual accounting, VAT, increased operational complexity.

By consolidating LMNP and SAS on an integrated platform (€18/month) and keeping an accountant only for the SCI (€150/month for validation only with clean data), total cost drops to €168/month — saving €67/month versus multi-tool, and €132-332/month versus full-accountant.

The multi-workspace advantage

Multi-workspace architecture maintains strict separation between entities while offering a unified interface. Each workspace has its own dashboard, tax categories, documents, and exports.

But navigation between workspaces happens in one click. And critically, it becomes possible to obtain a consolidated view of the entire portfolio: LMNP rental income + SAS consulting revenue, visualized side by side, with trends and ratios calculated automatically.

This overview — impossible to obtain with separate tools without manual work — is often the first thing wealth management advisors request during their annual reviews.

The accountant question

This approach doesn't eliminate the accountant — it optimizes their intervention. Instead of paying for data entry and cleanup (which represent 70% of billable time), you only pay for validation, advice, and official filing.

The accountant receives clean, categorized data with pre-filled tax exports. Their typical feedback: "Keep doing this, it saves me 3 hours of cleanup." And their bill reflects this efficiency.