I would recommend a company limited by shares for your convenience store. You can register this type of company on your own by appointing yourself as the sole shareholder and sole director, or you can set it up with other people.
A limited company structure offers financial protection to business owners because the company itself is liable for debts. This means that you will only be personally liable for debts up to the value of your shares. Most shares have a nominal value of £1, so your liability depends on the number of shares you choose to issue.
When you start trading through your company, you will have to register for business taxes. You will pay Corporation Tax on all taxable income, and you can then pay yourself a salary and dividends from the remaining profit.
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