Advice on a company share document (one page)

I have a business (bistro) which is being sold to a friend
She is going to take over the shares in the company and begin running the company (after renovations which she is funding)
Her intention is then to buy the company in the coming months but she has not finalised the mortgage etc and so has had a solicitor draw up a document as a safeguard during the interim period
I would like professional advice on this document.