Online auction house for a niche

Sellers pay you commission on items that sell, often with listing or photography fees. Buyers usually pay a buyer's premium on top of the hammer price.

A percentage of the hammer price from the seller, plus a buyer's premium, plus any fees for photography, listing or handling. Regular monthly sales and repeat consignors build income over time.

• Good knowledge of one collecting niche
• Photography and clear descriptions
• Organised record keeping
• Customer service with sellers and bidders

• Keep sellers' sale proceeds safe and pay them promptly; check whether you need a separate client account
• Check anti-money laundering registration with HMRC, which can apply to some high-value sales
• Check consumer law on descriptions, returns and distance selling for online sales
• Provenance and legality of items: stolen goods, ivory, firearms and some other items have strict rules
• Insurance for items in your care and public liability insurance; check your home insurance if you store stock at home
• Check with your landlord, mortgage lender or council if storing lots of stock at home

Startup costs are typically around £1,000 to £5,000, depending on your bidding platform, photography equipment, storage and insurance. These are estimates, so choose a niche you know well and begin with a small number of lots.

Check whether you need a separate client account for sellers' proceeds, and anti-money laundering registration with HMRC. Also check consumer law on descriptions and returns, the legality and provenance of items, and insurance for items in your care.

Monthly revenue is typically around £800 to £4,000, depending on how many lots sell and your commission rates. The time needed is estimated from around 15 hours a week, covering listing, photography and dealing with sellers and bidders.