Answers:
Yess you can do a little concrete from top of you concrete to make all fully level and lay porcelain , if you can't install more concrete you can lay they way people laying tyler for bathroom just wet cement and porcelain this way even more stronger,
For a 5-hour hedge trimming job, you can expect to pay anywhere from £125 to £375 or more, depending on the hedge's size, condition, and accessibility, as well as the professional's hourly rate. hourly rates for hedge trimming typically range from £25 to £75, with some professionals charging more for complex or larger jobs
First don’t completely block the hole with expanding foam or bricks.
best option for filling behind is breathable draught-proofing membrane or insulation
use natural, breathable insulation like:
hemp fibre insulation
sheep's wool
wood
If block paving border have pointing behind and front tarmac shoud be strong if you don't do it still should be okay , but i always do it by myself bc it's make more tight