a pre-loved toy marketplace for families
PROJECT OVERVIEW
What this app does
A marketplace where people buy and sell pre-loved toys using picture-based listings and verified seller profiles. Buyer payments are held in escrow until delivery is completed and marked as delivered, after which the buyer can leave a star rating for the seller.
As an anonymous visitor, I can browse available pre-loved toys and view listing details and seller ratings
As a seller, I can view purchased listings and mark an order as dispatched
As a seller, I can have my completed-purchase ratings displayed to prospective buyers
As a buyer, I can browse available toys and view their pictures, condition, price, seller verification status, and ratings
As a buyer, I can add or update my profile picture
As a buyer, I can purchase a toy with payment held until delivery is completed
As a buyer, I can mark an order as delivered so the held payment can be released
As a buyer, I can leave a star rating after a completed purchase
As a seller, I can add or update my profile picture
As a seller, I can publish a pre-loved toy listing with multiple pictures
As a seller, I can complete identity verification and view my verification status
The following user counts are projected totals after one year of growth
2500
sellers
Registered marketplace participants who publish toy listings, complete identity verification, and manage sold orders.
7500
buyers
Registered customers who browse toys, make escrow-protected purchases, confirm delivery, and rate sellers.
1000
anonymous_visitors
Unregistered visitors who may browse toy listings, listing pictures, seller verification indicators, and ratings but cannot purchase or sell.
COST BREAKDOWN
How your requirements become a plan and a price
Momen doesn't give a vague quote: it first sizes the project's actual demand for each capability and resource, then costs each item out. The numbers in the 'Project demand' column below — their scale assumptions and derivations — are detailed in Scale & sizing
Minimum viable plan
PRO
PRO is required for purchase payments held in escrow until buyers confirm delivery.
See the capability-by-capability assessment ▾
PROJECT DEMAND
ALLOWANCE PROVIDED (COMPOSITION)
AI points add-on
x 0
0 points
not purchased
(plan/kit 5.0M points)
No requirement
$ 0
Outbound data transfer add-on
x 23
927.86 GB/mo
500GB × 23/year, amortized monthly
(plan/kit 10.00 GB/mo + add-on +917.86 GB/mo)
Add-on fills +917.86 GB/mo gap beyond plan/kit
$ 67.08
Object storage
add-on
x 0
3.31 GB
not purchased
(plan/kit 10.00 GB)
Covered by plan/kit (margin ~202%)
$ 0
Database storage add-on
x 0
484.94 MB
not purchased
(plan/kit 1.00 GB)
Covered by plan/kit (margin ~106%)
$ 0
single-tenant kit
x 0
1 req/s
not purchased
(plan/kit 25 req/s)
Covered by plan/kit (margin ~2400%)
$ 0
PRO
x 1
Pro is the minimum viable plan
Pro
(Plan tier: PRO)
See minimum viable plan above
$ 99
plan + add-ons · usage-based · no development cost
WHY MOMEN
Your options for this project
In the table below, the 'monthly infrastructure' for the self-built / AI routes is derived from the AWS list prices shown below, sized against this project's actual usage. Figures cover infrastructure and operations only — AI usage is billed separately and excluded here, so they don't match the $166.08/mo all-in above.
Current usage sizing
AWS list pricing
432.69 GB (first 100GB free)
Internet egress → 38.94
3.31 GB-month
S3 Standard → 0.08
0.48 GB-month
RDS gp3 storage → 0.06
2 × db.m6g.large (Multi-AZ) × 730h
RDS PostgreSQL db.m6g.large → 232.14
2 × t4g.large × 730h
EC2 t4g.large → 98.11
Total ≈ $369.33 / mo
Pure cloud resources
DEVELOPMENT COST
MONTHLY CLOUD INFRA ($/MO)
MONTHLY TOTAL (INFRA + OPS, EXCL. AI USAGE)
Traditional outsourcing / build in-house
about $120,000 - $170,000
≈ $369
Based on the AWS estimate above
≈ $2,369
Infra $369 + ops ~$2,000
4-6 months
5 / 5
Vibe Coding
about $20,000 - $27,000
≈ $369
Based on the AWS estimate above
≈ $1,869
Infra $369 + ops ~$1,500
hours
5 / 5
AI full-stack generation
about $8,000 - $11,000
≈ $369
Based on the AWS estimate above
≈ $1,869
Infra $369 + ops ~$1,500
hours
3 / 5
Off-the-shelf SaaS / vertical solution
$0
N/A
Priced per seat, not by cloud infra
≈ $16,000+
Per-seat pricing, tens of thousands of users
days
1 / 5
Momen
Recommended
$0
$166
All-in: egress / storage / auto-scaling; excludes AI usage
$166
hours
5 / 5
Servers, databases, traffic and storage are inherent infrastructure costs for this project — you pay them whether you outsource, use Cursor or Lovable, or build it yourself (self-built runs ≈ $369.33/mo at AWS list prices, often more), on top of the dev and ops staff you'd need to hire. Momen bundles all of it into $0/mo all-in and removes the need for an ops team.
The frontend can be generated with AI tools (Cursor, Lovable, etc.); the hard part is the backend — auth, database, scaling, data security and ops. Momen delivers a production-grade backend as a BaaS: keep the vibe-coding speed on the frontend, while the backend runs on proven infrastructure — reliable, with no self-hosting or ops.
SCALE & SIZING
What scale this estimate assumes, and how the numbers are derived
Cost depends heavily on usage volume. First see the key assumptions and business scenarios this estimate uses, then the full calculation derived from each scenario for every resource — all adjustable to your real situation
We assume a mature registered base of 10,000 accounts because this is a two-sided consumer marketplace with no explicit user count or transaction throughput. This uses the standard multi-seller marketplace anchor and covers both primarily buying and primarily selling accounts. If the launch has an existing audience or known transaction volume, this parameter can be adjusted accordingly.
We assume this marketplace grows through a standard gradual launch because no full pre-existing dataset or exceptional acquisition burst was stated. A 225-day equivalent is typical for a marketplace that accumulates accounts, listings, orders, and ratings progressively during its first year. If the launch imports an established marketplace's records or experiences a sharp campaign-driven burst, this parameter can be adjusted accordingly.
Evening Marketplace Activity
Evening Marketplace Activity
Evening Marketplace Activity
Evening Marketplace Activity
30
times/month
0.59 req/s
Peak load
We assume marketplace discovery and purchase activity forms a distinct daily three-hour scenario because families usually browse consumer marketplaces during a broad evening period rather than at one synchronized instant. Anonymous discovery and signed-in purchasing occur in parallel but have different purposes and participant scales, so they are separated. The duration is 10,800 seconds and the scenario occurs on all 30 days of a typical month. If usage is concentrated into a shorter campaign window, these parameters can be adjusted accordingly.
Main impact: Peak Concurrency
The scenarios above set the assumptions for each resource; below is the full calculation derived from them. Click to expand each item.
DEVELOPMENT SCOPE
How this app works
What exactly does this budget support? Broken down by business scenario, showing the pages, data tables, automation flows and AI assistant behind each one
A seller reviews paid sales and marks a prepared order as dispatched.
Marketplace Browse Page
users
A seller reviews existing inventory and publishes a pre-loved toy with pictures.
Marketplace Browse Page
users
publish_listing
A seller checks their verification state and starts an identity check when not yet verified.
Marketplace Browse Page
users
publish_listing
A seller reviews their profile and uploads or replaces the picture shown with their marketplace identity.
Marketplace Browse Page
users
publish_listing
A buyer opens a completed purchase and leaves one star rating for its seller.
Marketplace Browse Page
users
A buyer reviews an order and confirms completed delivery so held funds can be released.
Marketplace Browse Page
users
A buyer compares toys, reviews a seller's purchase-backed ratings, and starts an escrow-protected purchase.
Marketplace Browse Page
users
A buyer reviews their account profile and uploads or replaces a profile picture.
Marketplace Browse Page
users
publish_listing
Public visitors browse available toys, open listing details, and review seller ratings without registering.
Marketplace Browse Page
users
publish_listing
page
data_table
action_flow
Rate Purchase Page
Completed-order page where a buyer can leave a purchase-backed seller rating.
Seller Sales Page
Seller order queue for reviewing sold toys and marking them as dispatched.
Buyer Orders Page
Buyer order history with delivery state and escrow-release confirmation.
Seller Verification Page
Seller page for checking verification status and starting identity verification.
Seller Dashboard
Seller workspace for reviewing inventory and publishing toy listings with pictures.
Profile Settings Page
Account page for viewing and changing the user's marketplace profile picture.
Listing Detail Page
Detailed toy listing with seller context, ratings, pictures, and the purchase action.
Marketplace Browse Page
Public catalogue for finding available pre-loved toy listings.
FAQ
What you might want to know about this project
The Q&A below is generated by AI based on this project's type, features and scale
How are sellers verified?
Are ratings restricted to completed purchases?
How do uploaded pictures affect capacity?
Does the design include true escrow payments?
What will drive this marketplace's resource usage most?
Copy to discuss with AI
Challenge & re-estimate
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