Since your priority is one platform that combines property management and full accounting, and you specifically want to track income and expenses at the individual unit level (not just by property), I'd focus on software that uses a true property → unit → tenant accounting structure.
Here are the strongest options.
1. Buildium (Best overall for small to midsize landlords)
For someone with a duplex today who may add more rentals later, this is probably the strongest all-around choice.
Why it fits your requirements:
- Native double-entry accounting
- Income and expenses tracked by property and individual unit
- Bank reconciliation
- Accounts payable
- Vendor management
- Rent collection automatically posts to the ledger
- Security deposit accounting
- Owner and tax reports
- 1099 preparation
For your duplex, each side can be set up as its own unit with separate ledgers and tenant histories, while still rolling up into property-level financial reports. Buildium is also designed to scale from a handful of units to thousands.
Best for: Investors planning to grow beyond just one or two rentals.
2. DoorLoop (Excellent accounting interface)
DoorLoop has become popular because its accounting feels much closer to dedicated bookkeeping software than many landlord apps.
Features include:
- Unit-level income and expense tracking
- Full general ledger
- Chart of accounts
- Bank reconciliation
- Bill payment
- Financial reporting
- Maintenance management
- Tenant portal
It also supports customizable accounting structures while remaining relatively easy to learn.
Best for: Self-managing landlords who care as much about accounting as operations.
3. Rent Manager (Most powerful accounting)
Rent Manager is known for having one of the deepest accounting systems in the property management space.
It includes:
- True double-entry accounting
- Unit-level ledgers
- Department/property/unit reporting
- Budgeting
- Work orders
- Purchase orders
- Extensive financial statements
The trade-off is a steeper learning curve than Buildium or DoorLoop.
Best for: Landlords expecting to own dozens of units.
AppFolio's accounting is tightly integrated with leasing, maintenance, and rent collection.
It offers:
- Per-unit accounting
- Automated rent posting
- Vendor payments
- Bank reconciliation
- Detailed owner reporting
- Excellent dashboards
The downside is that AppFolio is generally aimed at larger portfolios and typically isn't cost-effective for someone with a single duplex.
Best for: Professional property managers or larger portfolios.
TenantCloud is more affordable while still including:
- Income and expense tracking
- Unit organization
- Maintenance tracking
- Rent collection
- Basic accounting reports
Its accounting is less comprehensive than Buildium or DoorLoop, but many small landlords find it sufficient.
Best for: Budget-conscious owners with smaller portfolios.
Based on your duplex example
Suppose you own:
- Property: 123 Main Street
A strong system should let you record transactions like this:
| Transaction | Assigned to |
|---|
| Rent from Unit A | Unit A |
| Rent from Unit B | Unit B |
| Faucet repair in Unit A | Unit A |
| Painting common hallway | Property/Common Area |
| Roof replacement | Property (capital improvement) |
That lets you answer questions such as:
- Which unit is more profitable?
- How much maintenance has Unit A required versus Unit B?
- What is the net operating income for each unit?
- What expenses are shared across the entire property?
Not every landlord-oriented platform supports this level of detail, so it's worth confirming before you commit.
My recommendation for your situation
Since you've just purchased your first duplex and want to keep everything—leasing, rent collection, maintenance, and accounting—in one application without needing QuickBooks, I'd narrow it to:
- Buildium – Best balance of accounting depth, ease of use, and room to grow.
- DoorLoop – Best if you want a modern interface with particularly strong built-in accounting.
- Rent Manager – Best if you expect to build a much larger portfolio and are willing to invest more time learning the software.
For a landlord starting with a duplex but planning to acquire additional rentals over the next few years, Buildium is the option I'd be most inclined to recommend because it provides robust accounting with unit-level tracking while remaining approachable for smaller portfolios.