For Merchants (BETA)

Financing,
Programmable.

With the FLEX-API, you can connect your systems directly to Flexvelop:
Create quotes, view contracts, automate processes—all from
your online store, CRM, or inventory management system.

REST

JSON

API Key Authentication

app.flexvelop.de/api/v1/merchant 
$ curl -X POST https://app.flexvelop.de/api/v1/merchant/offers \
  -H "X-API-KEY: flx_live_••••" \
  -d '{ "offer": { "customer_email": "m.berg@…",
        "items": [ … ] } }'
→ 201 Created
{ "token": "state", "open" }
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Offer sent
‍Thecustomer can accept immediately — purchase
possible at any time.

Resources

What the FLEX API Can Do.


The FLEX-API maps your Flexvelop business—using a standardized JSON format and pagination—directly within the systems you already use.

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Contracts

All active lease agreements, including status, terms, and customer information—read-only and always up to date.

GET

Icon Finance Orange
Products

Your Product Catalog via API: Create, search, and update products—the foundation for generating quick quotes from your system.

GET · POST · PATCH

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Offers

Create new quotes on request — Flexvelop automatically sends them to your customers via email. Status and line items can be viewed at any time.

GET · POST

Use Case

What retailers are building with it.

With Flexvelop, your sales team can increase sales immediately. Inspire your customers on all channels with the best conditions for modern investments:

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Online Store Automation

Connect the FLEX-API to your online store, and financing offers will be generated fully automatically—without any intervention from your team.

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Quotes Directly from the CRM

Your sales team creates financing quotes directly from the CRM—just one request, and the quote is sent to the customer.

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Contract Overview in Your Own System

Sales and Support can view the status of all contracts and quotes directly in your inventory management system—without having to log in to the portal.

La Marzocco Linea Classic S, 2-group espresso machine

La Marzocco Linea Classic S · 2-group

Item No. LM-648303

€10,000.00 , excluding VAT

Interactive Example

FLEX as a payment method at checkout.

Rent Instead of Buying — Right Next to PayPal & Co. The FLEX-API automatically checks the shopping cart: It identifies devices available for rent, separates one-time costs, and immediately shows your customers the appropriate monthly payment.

Shopping cart 4 articles
1 × La Marzocco Linea Classic S · 2-group Available for rent 10,000.00 €
2 × Mahlkönig E65S espresso grinders available for rent €4,000.00to €2,000.00
1 × Barista Accessory Set one-time 180.00 €
Equipment14,000.00 €
One-time fees€180.00
Total 14,180.00 €

All prices exclude sales tax.

Select a payment method

Interactive Example

API Keys & Security

Full control over every access attempt.

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Authentication via API Key
Each request includes your key in the X-API-KEY header—no session, no login. You create and revoke keys yourself in the merchant portal.

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Strict client separation
Each key can access only its own data. The API returns a 404 error for quotes or contracts from other merchants.

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Encrypted Transmission
Every request is transmitted via HTTPS using TLS encryption. Your data and that of your customers remains protected.

API Key
Manage Your FLEX-API Access
Dealer Portal
API Key · Online Store
flx_live_••••••••7f2a
active
Created on March 12, 2026
API Key · Development
flx_live_••••••••b41c
active
Created on March 12, 2026

Interactive Example

Open-plan design

Made for your development team.

The FLEX-API is intentionally designed to be open—it’s not a black box or a modular system. Its development team integrates the interface into your systems to the exact extent that fits your processes. We’ll help you with the integration.

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Once your account has been activated, you can find the complete technical documentation directly in the dealer portal.

REST
‍Clearresources, predictable responses — in accordance with industry standards.

JSON
‍Aformat for requests and responses. Nothing more, nothing less.

X-API-KEY
Header-based authentication — Your key identifies you with every request.

/api/v1
‍Versionedand stable — Extensions won't break your integration.

A Look at the API

Endpoints you'll understand right away.


Clear resources, predictable answers.
Select an endpoint and view the example.
‍

POST
/api/v1/merchant/offers
Create and Send a Quote
GET
/api/v1/merchant/offers
List offers by page
GET
/api/v1/merchant/offers/:offer_token
Check the status of an offer
GET
/api/v1/merchant/contracts
View Current Contracts
GET
/api/v1/merchant/products
Browse the product catalog
RequestPOST /api/v1/merchant/offers
X-API-KEY: flx_live_••••••••
Content-Type: application/json

{
  "offer": {
    "customer_email": "m.berg@nordholz-buero.de",
    "cc_emails": "buchhaltung@nordholz-buero.de",
    "items": [{
      "name": "MacBook Pro 14\"",
      "description": "M3, 16 GB RAM",
      "price": "1999,00",
      "amount": 2
    }]
  }
}
Answer201 Created
{
  "token": "OFF-8KD2QP",
  "state": "open",
  "customer": "m.berg@nordholz-buero.de",
  "items": [
    { "name": "MacBook Pro 14\"", "price_in_cents": 199900, "total_quantity": 2 }
  ]
}