Preparing your item for sale It's worth spending time preparing your item for sale. Depending on the item, give it a good clean and polish, or get it professionally cleaned. If possible repair any damage that may reduce the value of your item, and check all the functions are working. Finally, if applicable, gather together all related paper work in readiness: e.g. certificate of authenticity, warranties etc. If you have any old receipts for work done it's worth collecting these together as well - they help reassure the buyer that you are an organised individual who has taken care of the item.