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The reselling course

Everything that decides whether a reselling business works

38 guides in 8 parts, written to be read in order. It starts where profit is actually decided — at purchase — and works forward through margin, listings, shipping, disputes, growth, and the compliance questions most sellers meet too late. Each part assumes the one before it.

Start at part one or jump to any part below

Not sure where to start? Eight questions, three minutes: find out whether capital, supply, or time is the thing actually holding you back.

Guides
38
Parts
08
Reading time
About 7 hours
Cost
Free, no signup

The running example

The Halstead lot

One hundred and eighty items bought for $260 at a house clearance in March: around 120 paperbacks, 30 pieces of kitchenware, twenty-two LPs, two mid-century table lamps, and a boxed film camera.

It is followed through every part of this course — valued, listed, shipped, disputed, aged, and finally accounted for — so each idea lands on the same pile of stock rather than on a fresh hypothetical.

Part 01

Foundations

What a reselling business actually is, and the first decision that constrains every other one: where you sell.

03 guides · 39 min

By the end of this part you can

  • Judge whether a category can support a business before committing money to it.
  • Compare categories on margin per handling hour rather than on headline margin.
  • Choose a first sales channel from evidence about your own inventory rather than from popularity.
  • Recognise the point at which a second channel adds profit rather than only work.

Part 02

Sourcing and inventory

Profit is decided at purchase. Valuing stock before you buy it, handling bulk lots, spotting fakes, and clearing what you got wrong.

05 guides · 61 min

By the end of this part you can

  • Choose sourcing channels on the trade-off between price, volume, and your own time.
  • Set a maximum bid backwards from realistic net proceeds instead of from hope.
  • Value a bulk lot you cannot itemise, and price in the share that will never sell.
  • Run a repeatable authenticity check before money changes hands.
  • Identify and clear aged stock on a schedule rather than on impulse.

Part 03

Money and margin

Fees, pricing, cost of goods, and cash flow — the arithmetic that decides whether a category is a business or an expensive hobby.

05 guides · 61 min

By the end of this part you can

  • Break a marketplace payout into its component deductions and predict it before it lands.
  • Price from sold data and hold a floor stated in currency rather than percentage.
  • Track cost per item so that profit by category becomes visible.
  • Model your cash conversion cycle and see the trough coming.
  • Run the business on turns and return on capital rather than on revenue.

Part 04

Listing quality

Getting found, earning the click, describing an item so accurately nobody sends it back, and diagnosing the ones that still will not sell.

06 guides · 69 min

By the end of this part you can

  • Clean, test, and prepare stock without destroying the value you are preparing.
  • Write titles in buyer vocabulary that survive marketplace search.
  • Complete structured attributes so that filters cannot exclude you.
  • Grade and describe condition accurately enough to make not-as-described claims rare.
  • Diagnose a stalled listing as a traffic, click, or conversion problem and fix only that.

Part 05

Shipping and fulfilment

Postage as a pricing decision, packing that survives the network, crossing borders, and what to do when a parcel goes missing.

04 guides · 46 min

By the end of this part you can

  • Price delivery against volumetric weight and carrier bands rather than guessing.
  • Pack fragile goods to survive an automated network, with evidence that supports a claim.
  • Decide whether international selling suits your categories, and open destinations deliberately.
  • Run a carrier claim that succeeds while keeping the buyer resolved separately.

Part 06

Service, standing, and systems

Disputes, fraud, account health, and the record structure — SKUs, storage, cross-listing — that stops a growing inventory from breaking under its own weight.

06 guides · 70 min

By the end of this part you can

  • Respond to a dispute in the way most likely to close it without escalation.
  • Read your seller metrics for direction rather than waiting for a threshold breach.
  • Recognise the common seller-targeted scams and keep evidence before a dispute exists.
  • Design a SKU and storage scheme that still works at ten times the stock.
  • Cross-list across channels without overselling the same unit twice.
  • Move inventory off spreadsheets without losing history or creating duplicates.

Part 07

Demand and growth

Buying ahead of the season, discounting without destroying margin, turning transactions into returning buyers, and raising throughput without raising hours in proportion.

05 guides · 58 min

By the end of this part you can

  • Measure your own seasonality and buy counter-seasonally with an exit date set in advance.
  • Judge a promotion on profit rather than on units.
  • Build the specialisation and service habits that produce returning buyers.
  • Find the listing bottleneck and raise throughput by batching before automating.
  • Judge honestly whether an owned storefront is worth the traffic it demands.

Part 08

Business, compliance, and what comes next

Structure, registration, consumption tax, and risk — the questions worth understanding before you take them to an accountant or a broker — and the decision about whether this becomes your income.

04 guides · 45 min

By the end of this part you can

  • Recognise when selling has become a business, and what tends to follow from that.
  • Keep records in a form that survives a question from a tax authority.
  • Name the exposures a reselling business carries, including the one no policy covers.
  • Arrive at an accountant with specific questions rather than a shoebox.
  • Test whether the business could replace an income before betting on the answer.

Course files

Take these with you

Free, no sign-up, no email. Open formats you can edit — spreadsheets and plain text, not locked PDFs.

Shorter reads

The course covers each subject end to end. For a single question answered quickly, the blog goes deep on individual problems, and the free calculators handle the arithmetic — fees, margin, and what a sale actually nets after everything comes out of it.

Start with 25 items. Stay for 25,000.

Free for 25 items · No card · Cancel from your account page.

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