UK Landlord Forum / Life

I would be grateful for some guidance on having a bare license to occupy. A relative is moving in to the property for a short period - 3 - 4 months while it is going through probate. Is a bare license required at all? For example to say they must keep the pay for any heating / lighting they use, take reasonable care and keep property clean etc.If so do I have to have a solicitor draw up the agreement or can I buy something with standard wording.
Many thanks for your help.