Should I use Shopify or build my own?

Shopify. Always. Even for technical founders. The hours saved on infrastructure are worth more than any custom-build advantage at your stage.

Only if you can build a brand on top of the dropship product. Pure dropshipping (no brand, no value-add) is a race to the bottom on margin.

Amazon vs DTC store — pick one or run both?

Run both, but make Amazon the discovery channel and DTC the retention channel. Amazon brings impulse buyers; your job on Amazon is to convert at the search-result level. Once they've bought once, the post-purchase insert + email capture builds your DTC list, where you control the margin and the relationship. Going DTC-only foregoes Amazon's huge intent traffic; going Amazon-only leaves you exposed to a platform that can change rules overnight.

When do I add a subscription / replenishment offer?

Once you have ≥200 customers who've bought twice or more on the same SKU within 90 days. That data tells you the natural repurchase cycle, and the subscription becomes a lower-friction version of behaviour customers are already showing. Adding it earlier — before the data exists — typically results in low subscribe rates and high cancellations because you've guessed wrong on cadence.

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Business Model

Building an ecommerce business

Ecommerce is harder than it looks. The margin math is unforgiving, the cash cycle is brutal, and 'just do ads' is bad advice for first-time founders. This is the realistic version.

By Priya Ranganathan · Last updated May 19, 2026

Who this is for

Founders launching a physical or digital ecommerce store.

What you'll learn

Picking a product that has margin space
Realistic cash flow for inventory businesses
First sales channel without paid ads
Retention vs acquisition in ecommerce

Calculate your break-even

Pick a product with margin space

The math: you'll lose 30-40% of revenue to platform fees, shipping, returns, ads, and customer support. You need at least 50-60% gross margin to survive at scale.

Practical product filters:

Cost to make < 20% of retail price. Anything above that is fragile.
Lightweight if shipping internationally.
Doesn't need a huge size catalogue. Apparel without sizes is way easier than apparel with 6 sizes × 3 colors.
Has repeat-purchase logic. Consumables beat one-off purchases for LTV.

Don't pick a product with a great story but bad margin math. The margin math wins eventually.

Cash flow reality

Inventory-based ecommerce is brutal on cash flow. You pay your supplier in week 1, collect from customers over months 2-6, repeat.

Practical cash-flow rules:

Don't order more inventory than you can sell in 90 days. Stockouts are cheaper than dead stock.
Use SKU velocity to forecast. If a SKU sells 30/week, order 12-week supply, not 12-month supply.
Don't fund inventory with credit cards. The interest will eat your margin.

The Runway Calculator is doubly important for ecommerce because cash is locked in inventory.

First sales channel

Paid ads to a new ecommerce store usually lose money. The channels that work for first $10k of sales:

Your existing network. "I made this; want to try?"
One niche community that loves this category.
Press / influencer outreach to ~20 micro-influencers (10k-50k followers, your ICP).
SEO for very specific product searches (months 2-12).
Marketplace presence (Etsy, Amazon, etc.) for specific categories.

Ads can work — eventually — once you have data on which products convert, which audiences buy, and what your real [CAC payback](/glossary/payback-period) is. Not day one.

Retention is the whole game

Acquisition gets all the attention. Retention is where ecommerce profitability lives.

Practical retention levers:

Email/SMS post-purchase flow — 6-8 messages that drive the second purchase.
Subscription / replenishment for consumables.
Bundles that increase AOV (average order value).
Personalised recommendations based on first purchase.
The actual product being good enough that they want more.

If your first-purchase cohort doesn't make a second purchase within 90 days, your business is on a treadmill — every dollar you earn goes back into acquiring the next customer.

Returns, fulfilment, and the operational rabbit hole

New ecommerce founders underestimate the operational tail of every sale. The visible work is "make sale, ship product." The invisible work is the third of revenue that doesn't behave: returns, customer support, breakage, fraud.

Returns benchmarks by category:

Apparel: 20-30% return rate (the killer).
Beauty / cosmetics: 5-10%.
Home goods: 5-15%.
Consumables: <5%.

Every return costs you: outbound shipping, return shipping (often you eat it), restocking labour, and 20-40% of returned inventory unsellable. Model returns into your unit economics from day one. If your gross margin doesn't survive a 25% return rate, apparel is the wrong category for you.

Fulfilment paths and when each makes sense:

Self-fulfil from home — fine to ~50 orders/week. Above that, you stop being a founder and become a packer.
Local fulfilment company — sensible from 50-500 orders/week. Predictable per-order pricing.
Marketplace fulfilment (Amazon FBA, ShipBob, Shopify Fulfilment Network) — when you cross 500/week or need 2-day shipping as a product feature. Margin hit but operational sanity.

Customer support is a product surface. Founders who treat support as a cost centre underinvest and watch retention drop. Founders who treat support as part of the product (fast replies, generous refunds for small mistakes) see retention compound. The 30-day money-back guarantee that costs 4% in refunds typically gains 8-15% in conversion.

Step-by-step action plan

Do these, in order

1Test the margin math on your first product
2Pick one non-paid channel for the first $10k of sales
3Build the post-purchase email flow before you launch
4Track repeat-purchase rate from week one

Frequently asked questions

Should I use Shopify or build my own?: Shopify. Always. Even for technical founders. The hours saved on infrastructure are worth more than any custom-build advantage at your stage.
Should I dropship?: Only if you can build a brand on top of the dropship product. Pure dropshipping (no brand, no value-add) is a race to the bottom on margin.
Amazon vs DTC store — pick one or run both?: Run both, but make Amazon the discovery channel and DTC the retention channel. Amazon brings impulse buyers; your job on Amazon is to convert at the search-result level. Once they've bought once, the post-purchase insert + email capture builds your DTC list, where you control the margin and the relationship. Going DTC-only foregoes Amazon's huge intent traffic; going Amazon-only leaves you exposed to a platform that can change rules overnight.
When do I add a subscription / replenishment offer?: Once you have ≥200 customers who've bought twice or more on the same SKU within 90 days. That data tells you the natural repurchase cycle, and the subscription becomes a lower-friction version of behaviour customers are already showing. Adding it earlier — before the data exists — typically results in low subscribe rates and high cancellations because you've guessed wrong on cadence.

Related resources

Returns math for a sub-$50 DTC product

Five DTC margin traps that look like growth

Related tools

Break-even Calculator

LTV:CAC Calculator

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