Build vs. buy: an honest answer
If you're considering building your own inventory and operations platform instead of paying from $999/month for Rilk Pro, here is the scope of work, laid out factually, so you can make an informed decision.
What you're actually building
Rilk runs 50+ sales channels today, arriving over four separate transports: 10 live native marketplace integrations built in-house, retailers on the Mirakl platform, retailers on SPS Commerce, and direct EDI connections to Home Depot, Lowe's, Macy's, Overstock and Zoro. Each integration is its own data model, its own quirks, its own quarterly drift — and each transport is a separate commercial relationship on top of the engineering. Each marketplace has its own approval gauntlet: Rilk is a listed app in the Amazon Selling Partner Appstore, which took the better part of a year and multiple rounds of Amazon review, including a data security assessment before Amazon grants access to buyer shipping data, and every other major marketplace runs its own review.
Beyond the connections themselves, an operations platform has to handle order ingestion and status synchronization across marketplaces whose status transitions don't align, settlement reconciliation that matches every fee line back to the unit that earned it, a returns workflow with several outcomes and sub-paths, per-serial cost tracking for anything serialized, multi-carrier shipping with rate shopping and native Buy Shipping integrations, purchase orders with landed cost allocation for both domestic and overseas vendors, and reporting that ties all of it to settlement-reconciled actuals rather than estimates.
What it actually costs to build
Honest range, based on engineers who have actually tried, assuming you're trying to match Rilk's current scope across 50+ channels and four transports, full settlement reconciliation, regrading, returns, landed cost, and multi-carrier shipping: a single experienced engineer needs 3-5 years to reach a v1 that matches the breadth and depth, and will more realistically ship 4-6 channels and stop. A small team of 3-5 engineers needs 24-36 months for a handful of marketplaces, and 4-6 years for 50+ channel parity. An in-house team replacing a vendor needs 18+ months minimum for even a narrow subset.
At a $150K/year fully-loaded engineer cost, the floor for a narrow v1 is $450K; a team targeting Rilk's full breadth is $3M-$7M before ongoing maintenance. Rilk's Pro plan — the full reselling workflow for one company — starts at $999/month, or $11,988/year at the minimum.
What you're forgetting
The visible scope is roughly two-thirds of the actual work. Marketplace rules change quarterly, carrier rate structures change annually, and regulatory drift (1099-K thresholds, sales-tax nexus rules, customs codes) forces ongoing changes. Security obligations around customer PII, marketplace tokens, and payment data carry real handling requirements, and customer support load and the "I want X" feature backlog both grow the platform continuously.
Who should still build
Some sellers should: a single-channel, single-carrier operation with no returns needs a label printer, not an operations platform. A business with genuinely unique requirements — hazmat, regulated medical devices, cold-chain perishables — should build the unique parts and integrate vendor tools for the rest. And a team whose actual business is building an operations platform should build one.
For everyone else — multi-channel resellers, refurbishers, importers, and brand operators selling across two or more channels with returns and shipping — buying is faster, cheaper, more reliable, and leaves more time for the part of the business that actually makes money.
What Rilk actually costs
Public, per-account pricing, no "talk to sales" gate for standard plans. Free covers your first 500 orders a month at $0, no credit card required to start. Pro starts at $999/month and adds warehouse & bin management, serial number lifecycle tracking, purchase orders & regrading, FBA & WFS shipments, and settlement-reconciled per-unit P&L, with every order shipped metered at $0.30 ($0.05 if Amazon-fulfilled) credited against the minimum. Ultimate is custom-quoted for businesses running more than one company or selling through retailer EDI, with all platform features, a dedicated customer success manager, and priority support. No per-user seat fees, no per-channel surcharges, no setup costs, no implementation team.