Property: HDB Minimum Occupation Period (MOP) Tracking

[jcleow]

Summary

Add Minimum Occupation Period (MOP) tracking for HDB properties. The 5-year MOP is a critical constraint that affects when owners can sell or rent out their HDB flat.

Why This Matters

• Cannot sell HDB before MOP completion
• Cannot rent out entire unit before MOP (only rooms allowed after 3 years for some schemes)
• Affects exit strategy and liquidity planning
• Interacts with SSD (Seller's Stamp Duty) timing

MOP Rules

Flat Type	MOP Duration	Start Date
BTO / SBF / Sale of Balance	5 years	Key collection date
Resale (with CPF grant)	5 years	Key collection date
Resale (no grant, 1st timer)	5 years	Key collection date
EC (Executive Condo)	5 years	TOP date
DBSS	5 years	Key collection date

Rental Restrictions During MOP

• Years 1-3: Cannot rent any part
• Years 3-5 (some schemes): Can rent out rooms (not whole unit)
• After MOP: Can rent out entire unit

Proposed Data Fields

interface MOPConfig {
  propertyType: 'hdb_bto' | 'hdb_resale' | 'ec' | 'private'
  keyCollectionDate: string        // YYYY-MM format
  mopDurationYears: number         // Default 5 for HDB
}

// Computed
interface MOPStatus {
  mopEndDate: string
  monthsRemaining: number
  canSell: boolean
  canRentRooms: boolean
  canRentWholeUnit: boolean
}

UI Integration

• Display MOP end date prominently for HDB properties
• Countdown showing months remaining
• Visual indicator (progress bar or badge)
• Warning when setting sale date before MOP
• Warning when enabling rental income before MOP allows it
• Alert/notification when MOP is approaching completion

Sale Date Validation

if (propertyType.startsWith('hdb') && saleDate < mopEndDate) {
  showWarning("Cannot sell HDB before MOP completion on " + mopEndDate)
}

Acceptance Criteria

• MOP end date calculated from key collection date
• MOP countdown displayed for HDB properties
• Warning when sale date is before MOP
• Rental restrictions enforced based on MOP status
• Clear visual indicator of MOP status (pending/completed)
• Notification when MOP is about to complete

Interaction with Other Features

• SSD (Property: Support ownership splits (Joint Tenancy vs Tenancy in Common) #170): Both affect optimal sale timing
• Rental Income (Property: Rental Income Modeling for Investment Properties #171): Rental restricted during MOP
• Sale Proceeds: Sale blocked until MOP complete

Labels

property, enhancement, P2, hdb

[linear]

ASS-73