Get a good lawyer.
You are up against the Town Council, HDB and the contractors.
You are no match against their combined brain power to
negotiate.
They will generously agree to pay all your medical expenses,
just to shut you up. If you want to sue for more, then you need a
good lawyer, to counter their vile-ness.
contractors are not con. however they are no sitting duck too.
frankly, they are covered with insurance so you are against
the insurance, not them. You have to prove that it is their
neligence etc. Shld your friend trepass a worksite, then
the cases would be different.