How about this:
"Dear neighbour
Regarding the right for you to dry clothes on my property - I am willing to concede this right.
However please note:
The wording in the deeds make no mention of the right to dry laundry other than clothes on my property so this right does not extend to the drying of towels, bedlinen or any other fabric that is not clothing.
The wording in the deeds make no mention of the right to store any clothes-drying equipment not currently in active use for drying clothes, or to leave dry clothes on my property.
Also given that your clothes can only be on my property for the express purposes of drying, there is no right for your clothes to be on my property on any rainy day.
I have the right to enjoyment of my property and may charge as I see fit for access to and usage of my property for any purpose not covered by the right in the deeds.
My prices are as follows:
To keep a washing line or clothes airer on my property when not in use for drying clothes: £50 per day if placed so as not to disrupt my use of my parking space. £200 per day if placed so as to disrupt my use of my parking space.
To keep dry clothes on my property after they are dry: £10 per item per day or part thereof.
To keep clothes on my property when drying is not possible ie when it is raining: £10 per item or part thereof.
To dry items of laundry other than clothes, eg Towels £10 per item per day or part thereof.
These prices shall be clearly displayed in the area in front of my house and you are welcome to choose to use any of these additional services offered.
You will be invoiced weekly for any such serviced used, payment to be made to (add your account details) within 30 days of invoice.
If you fail to pay I shall have legitimate right to retain possession of any of your clothes or clothes drying equipment to sell in order to recoup the unpaid debt. Unpaid debts may further be pursued through the courts."
Nb I am not a legal expert. I have no idea if this would be enforceable.