a multi-seller marketplace app
PROJECT OVERVIEW
What this app does
This project is a multi-seller marketplace app where visitors and buyers can discover products, review listing details, and place paid orders. Sellers can publish products and fulfill resulting orders, while platform administrators review listings before they become publicly available.
As an anonymous visitor, I can browse approved products and view product details
As a buyer, I can review a product and place a paid order
As a buyer, I can view my order history and fulfillment status
As a seller, I can create a product listing for review
As a seller, I can view my listings and their moderation status
As a seller, I can review and fulfill orders containing my products
As a platform administrator, I can approve or reject pending product listings
The following user counts are projected totals after one year of growth
20
platform_admins
Internal marketplace staff who review product listings and enforce publication decisions.
1980
sellers
Registered merchants who publish products and fulfill orders.
8000
buyers
Registered customers who browse products, place orders, and review their purchases.
1000
anonymous_visitors
Public visitors who browse approved products without signing in.
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
Paid marketplace orders require payment capabilities available on PRO.
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 14
552.13 GB/mo
500GB × 14/year, amortized monthly
(plan/kit 10.00 GB/mo + add-on +542.13 GB/mo)
Add-on fills +542.13 GB/mo gap beyond plan/kit
$ 40.83
Object storage
add-on
x 0
7.07 GB
not purchased
(plan/kit 10.00 GB)
Covered by plan/kit (margin ~41%)
$ 0
Database storage add-on
x 0
353.42 MB
not purchased
(plan/kit 1.00 GB)
Covered by plan/kit (margin ~183%)
$ 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 $139.83/mo all-in above.
Current usage sizing
AWS list pricing
216.98 GB (first 100GB free)
Internet egress → 19.53
7.07 GB-month
S3 Standard → 0.16
0.35 GB-month
RDS gp3 storage → 0.04
2 × db.m6g.large (Multi-AZ) × 730h
RDS PostgreSQL db.m6g.large → 232.14
2 × t4g.large × 730h
EC2 t4g.large → 98.11
Total ≈ $349.98 / mo
Pure cloud resources
DEVELOPMENT COST
MONTHLY CLOUD INFRA ($/MO)
MONTHLY TOTAL (INFRA + OPS, EXCL. AI USAGE)
Traditional outsourcing / build in-house
about $100,000 - $145,000
≈ $350
Based on the AWS estimate above
≈ $2,350
Infra $350 + ops ~$2,000
4-6 months
5 / 5
Vibe Coding
about $18,000 - $24,000
≈ $350
Based on the AWS estimate above
≈ $1,850
Infra $350 + ops ~$1,500
hours
5 / 5
AI full-stack generation
about $7,000 - $10,000
≈ $350
Based on the AWS estimate above
≈ $1,850
Infra $350 + 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
$140
All-in: egress / storage / auto-scaling; excludes AI usage
$140
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 ≈ $349.98/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 10,000 registered accounts because the product is a two-sided marketplace with no explicit user count or transaction-throughput signal, and this is the standard mature scale anchor for an indie marketplace. If the expected buyer pool, seller onboarding target, or transaction volume differs, this registered-account parameter can be adjusted accordingly.
We assume 225 effective accumulation days because a new marketplace commonly follows standard linear growth as buyers, sellers, listings, and orders build over its first year. If the launch includes a full pre-existing catalog or experiences a concentrated recent growth burst, this parameter can be adjusted accordingly.
Evening Buyer Activity
Weekday Seller Operations
Evening Buyer Activity
Evening Buyer Activity
30
times/month
0.37 req/s
Peak load
We assume registered buying and order-history review coexist across a three-hour evening period because consumer purchasing and post-purchase checking commonly peak after daytime commitments. They are separated into distinct purposes because checkout creates transactional demand while history review is read-only and has a different participant count. The scenario occurs daily without an externally synchronized start. If the marketplace serves business buyers or has a flash-sale rhythm, the timing and concentration 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
Administrator flow for reviewing pending seller listings and recording decisions.
Marketplace Browse Page
users
Seller flow for reviewing paid orders and updating their fulfillment states.
Marketplace Browse Page
users
Seller flow for reviewing existing listings and submitting a new product.
Marketplace Browse Page
users
Buyer flow for reviewing previous purchases and fulfillment status.
Marketplace Browse Page
users
Registered-buyer flow from product discovery through paid order creation.
Marketplace Browse Page
users
create_marketplace_order
Public discovery flow for browsing approved products without an account.
Marketplace Browse Page
users
page
data_table
action_flow
Listing Moderation Page
Administrative queue for reviewing and deciding seller product submissions.
Seller Orders Page
Seller queue for reviewing paid orders and recording fulfillment progress.
Seller Listings Page
Seller workspace for creating listings and reviewing their publication status.
Buyer Orders Page
Private history of orders placed by the signed-in buyer.
Product Detail Page
Product information page with the registered-buyer checkout entry point.
Marketplace Browse Page
Public product catalog for finding approved marketplace 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
Can the estimated user scale be changed?
How do product images affect the plan requirements?
Does the marketplace support multi-seller carts?
Which marketplace features are included?
What most affects resource usage for this marketplace?
Copy to discuss with AI
Challenge & re-estimate
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