Provide precise and accurate data pertaining to your future target group and the advantages to clients, possibly even multiple advantages.
This information should be part of your sales business plan.
Your quality and price range are key to the viability of your products or services. Sometimes comparable offers (products / services) will cost more. Describe the price segment you want to see your online store in. Provide data on details like the purchase price, operating costs, personnel costs, financing costs, etc.
Define your shop system (finished shop, rental shop or open source solution). Define your product groups (brand, label) or service.
An online shop thrives on regular updates (who runs it? Make your schedule clear for the start-up period; define the stages. Why did you choose an online shop to sell them (niche products, perhaps an online retail business plan is more lucrative)? How and where is the service provided (manpower, time, regional or national, is there a hotline available)?