hi bro,

in general it seem that your soil is a bit 'turun' or 'mendap' this can be avoid if the contractor properly do it properly.

Let start with :

Wall partition & car porch & drainage walkway:

If i just look at the wall partition only, it normally due to the contractor did put / 'tanam' horizontal besi (can be steel 'link' size 6 or 7, or can put steel Y10 ) between the existing wall and new wall. This always happened if the contractor did not put horizontal steel tanam at existing wall (about 1 feet) to old wall, it wall crack after few year. Secondly, the correct way to joint the new wall and old wall is to hack a bit the plaster of the old wall then, place your new batu bata then replaster again. hope you under stand.

Unfortunetly by looking porch picture, the crack is along between wall and porch, suspected your tanam turun a bit. Suspected also, your contractor did not lay down BRC steel at during the concrete. 

Drainage:

by looking at the picture, seem you fondation turun (suspected your contractor not properly do it, or you soil turun). To rectify this, hack the plaster then inspect whether your beam crack or not, if just plaster cracking, then just replaster.

Fence:

Mostly did is just plaster cracking due to the batu pasir crack. For the last picture, this is maybe due to plastering, from my experience , if we use batu pasir for fence we will always this kind of crack, the batu pasir itseld if crack causing the plastering crack. Hack the plaster and lay the 'wire/steel net' and replaster.

TQ

hi bro,

i believed your water leaking problem is due to water seep thru your concrete gutter that do not have water proofing.

for upah pasang pintu is normally RM100 and upah varnish or paint door is Rm150.

hi bro,

for you case, skim coat and painting, the upah cost about RM3K.