How to pave a small area but get maximum drainage / permeability
You can get permeable paving (sometimes sold as Sustainable Urban Drainage System (SUDS)) which looks like solid paving but has nibs on the edge of each block so the surface is self-draining. Some are rated for driveway or commercial car parking use, so no problems about the blocks moving. 

https://www.marshalls.co.uk/homeowners/driveways/permeable-paving