I plan to lay paving stones in my as a base for an inflatable hot tub. The area is 2.4 x2.4 m it is by a small garden wall. My question is, do I need to make a fall in the pavers when laying and if so, by how much? I intend to use 75 mm MOT type 1 compacted as a sub base then laying slabs on about a 50 mm full bed of mortar. Thanks.