ADU added to a rental Cost Segregation: Tax preparer handoff
Connect the property evidence to the return decisions without assuming filing work is included. Resolve separate new-unit construction from shared building and site systems using property-specific records.
The issue this scenario creates
An accessory unit may share services with an existing rental. Reconcile new construction and allocated shared costs without counting the same system in both buildings.
The main objective is to separate new-unit construction from shared building and site systems. A useful analysis makes the ownership and timeline understandable before anyone applies a reclassification estimate. Do not replace missing history with an assumed new purchase or a generic depreciation percentage.
Tax preparer handoff approach
Send the final study, reconciled basis, prior asset schedules, relevant dates, and unresolved issues together. Ask the preparer to confirm the implementation approach and any required election or accounting-method analysis. Explain the ownership and use history rather than expecting an asset spreadsheet alone to convey it.
The preparer evaluates current authority, applicable methods, bonus eligibility, loss limitations, state treatment, and any later sale effects. Assign filing tasks explicitly and distinguish study delivery from completion of the return. Retain final filed statements and schedules so a future preparer can determine what was actually implemented.
Scenario-specific evidence
Start with ADU plans, permits, contractor costs, utility routes, and completion records. Connect each record to the event it establishes. Explain conflicts and missing years rather than presenting a single unexplained number.
| Field | What to record |
|---|---|
| Main question | Separate new-unit construction from shared building and site systems |
| Source documents | Adu plans, permits, contractor costs, utility routes, and completion records |
| Known uncertainty | Duplicating shared utility costs across two studies |
| Event timeline | Original acquisition or transfer; changes in rental use; additions, removals, and prior filing events. |
| Reconciliation | Supported opening amount, relevant adjustments, land and separate assets, prior treatment, and the cost pool used in the report. |
Hypothetical example
A backyard unit connects to the main house's water and electrical service.
The review should guard against duplicating shared utility costs across two studies. Resolve that concern using the specific records above. The example illustrates a process question, not an available deduction or an actual completed client study.
Question to resolve before closing this task
Has the preparer confirmed the filing approach and received the final records rather than an earlier draft?
Write down the response and retain the supporting record. Assign an owner to any remaining issue and confirm whether it changes the study scope, projected benefit, delivery timeline, or implementation cost. A property report and a usable deduction are separate steps in the workflow.
Practical completion checklist
- Identify the actual property owner and reporting taxpayer.
- Preserve original records and explain missing information.
- Keep existing assets separate from later additions and replacements.
- Confirm the provider and return preparer have accepted the same basis reconciliation.
- Retain the final report and the schedules actually implemented.
References and scope
- IRS Publication 551: acquisition, transferred, and adjusted basis
- IRS Publication 527: rental use, conversion, and expense considerations
- IRS Publication 946: depreciation, ownership, methods, and timing
- IRS Instructions for Form 3115: accounting-method change procedures
These references explain the underlying tax framework. The checklists and scenarios on this page are editorial tools for gathering evidence, not quotations or asset-specific rulings from the IRS. The audit guide is examination guidance, not an official pronouncement of law or certification of a provider. A return preparer must apply current authority to the particular property, taxpayer, and filing year.