Draft Secured Loan Agreement

I’m lending a friend £200,000 so they can clear their mortgage, with the understanding that the loan will be repaid from the sale of their property within 12 months. To protect my position I want a watertight, UK-compliant contract and charge drafted by a legal professional... (Budget: £250 - £750 GBP, Jobs: Compliance, Contracts, Employment Law, Legal, Legal Consultation, Legal Review, Legal Writing, Property Law)