S

Solo Business Tax Code Simulator

4.30

Derivation Chain

Step 1 Career-based Solo Entrepreneur tax & business registration onboarding
→
Step 2 Tax differences based on business category code selection

Problem

When registering as a Freelancer or consultant after retirement, the chosen business category code determines simplified tax eligibility, VAT rates, and expense ratios (standard vs. simplified). The same 'consulting' work can result in $750–$2,250 in annual tax differences depending on the category code. However, there are over 1,000 category codes and the National Tax Service search tool is notoriously unfriendly, so retirees either pay a tax accountant $82+/month or choose a code by guesswork.

Solution

Users describe their career and work activities in natural language. The tool recommends 3–5 suitable business category codes and shows a comparison table for each code covering VAT (simplified vs. standard taxpayer), comprehensive income tax (simplified vs. standard expense ratio), and health insurance premium impact across estimated revenue brackets. It clearly shows 'if you register under this category code, your annual taxes will be X.'

Target: Ages 50–60, transitioning to Freelancer or Solo Entrepreneur consulting after retirement, first-time business registration, wanting to reduce tax accountant costs
Revenue Model: Category code recommendation + basic tax comparison free. Detailed first-year tax calendar PDF (filing deadlines & estimated prepayments) ~$3.75. Simple bookkeeping template package ~$7.40.
Ecosystem Role: Education
MVP Estimate: 2_weeks

NUMR-V Scores

N Novelty
4.0/5
U Urgency
4.0/5
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 (78%)

Tech Complexity
34.7/40
Data Availability
23.1/25
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 (61/100)

Competition
8.0/20
Market Demand
6.2/20
Timing
16.0/20
Revenue Signals
10.5/15
Pick-Axe Fit
12.0/15
Solo Buildability
8.0/10
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 [low] Backend [medium] Data Pipeline [low]
Dashboard