A

HomeTax Refund Self-Coach

4.30

Derivation Chain

Step 1 Digital administrative delegation
→
Step 2 Self-filing comprehensive income tax refunds without a tax accountant
→
Step 3 Integrated guidance including post-refund health insurance premium projections

Problem

Freelancers and rental income earners in their 50s pay 300,000–500,000 won (~$225–$375) to tax accountants every May for comprehensive income tax filing, even though many qualify for simplified expense rates or are eligible for refunds. However, the HomeTax interface is complex and they don't know which deductions apply, so they give up on self-filing. The bigger issue is that after receiving a refund, their health insurance premiums are recalculated based on reported income the following year, leading to unexpected premium increases.

Solution

Users enter their income type (employment/business/rental/other) and approximate amounts on a web interface, then receive step-by-step screenshot-level guidance through the HomeTax filing process, with specific coaching like 'enter this number in this field' at each step. After filing, the system automatically calculates and displays the expected refund amount along with projected health insurance premium changes for the following year.

Target: Ages 45–60, Freelancers, Solo Entrepreneurs, and real estate rental income earners with annual income under 40 million won (~$30,000), eligible for simplified expense rates, who feel their annual tax accountant fees are a waste
Revenue Model: Basic filing guide: Free. Health insurance premium change projection + tax-saving simulation Report PDF: 5,000 won (~$3.75) Per Transaction. Annual Subscription (pre-filing season alerts + income change tracking): 29,000 won (~$22).
Ecosystem Role: Education
MVP Estimate: 2_weeks

NUMR-V Scores

N Novelty
3.0/5
U Urgency
5.0/5
M Market
4.0/5
R Realizability
5.0/5
V Validation
4.0/5
NUMR-V Scoring System
N Novelty1-5How uncommon the service is in market context.
U Urgency1-5How urgently users need this problem solved now.
M Market1-5Market size and growth potential from proxy indicators.
R Realizability1-5Buildability for a small team with realistic constraints.
V Validation1-5Validation signal quality from competition and demand data.
Each dimension is scored 1-5 and weighted into grade S/A/B/C/D.
SaaS N=.15 U=.20 M=.15 R=.30 V=.20 Senior N=.25 U=.25 M=.05 R=.30 V=.15

Feasibility (70%)

Tech Complexity
29.3/40
Data Availability
20.4/25
MVP Timeline
20.0/20
API Bonus
0.0/15
Feasibility Breakdown
Tech Complexity/ 40Difficulty of core implementation stack.
Data Availability/ 25Practical availability and cost of required data.
MVP Timeline/ 20Expected time to ship a usable MVP.
API Bonus/ 15Bonus for viable public API leverage.
Total 100 points; below 50% is filtered out.

Market Validation (56/100)

Competition
8.0/20
Market Demand
6.2/20
Timing
14.0/20
Revenue Signals
10.5/15
Pick-Axe Fit
10.5/15
Solo Buildability
7.0/10
Validation Breakdown
Competition/ 20Signal quality from competitor landscape.
Market Demand/ 20Demand proxies from search and mention patterns.
Timing/ 20Fit with current shifts in tech, behavior, and regulation.
Revenue Signals/ 15Reference evidence for monetization viability.
Pick-Axe Fit/ 15How well the concept serves participants in a trend.
Solo Buildability/ 10Practicality for lean-team implementation.
Total 100 points; below 50 is filtered out.

Technical Requirements

Frontend [medium] Backend [medium] Data Pipeline [low]
Dashboard