Some great advice here! Many thanks to all for their input.
@ehsantl please let us know how you go with the project. It would be great to get an update when you make some progress. And I'm sure community members will be happy to provide more advice if you need a hand.
For whoever carious about what happened to my backyard, this is a end result after couple of years
Fence paint and screen + Paving + Deck + Screen for water tank + lots of bamboos
Thanks for your feedbacks
Wow, brilliant result @ehsantl. Thank you so much for coming back and sharing some photos. Looking forward to seeing what you tackle next!
Feel free to post anytime you need a hand with anything.