Advice wanted on possible subdivision

Hi guys,

I have a few questions about subdividing my land.  I have a double block and I'm thinking of selling off 1 block
and use this money to build 2 Units on the other block.

I need to get a rough Idea of all the costs involved to see if my plan will work out.

So the main question is how much is the going rate per  sqm  to build the units?

the other questions is how much will it cost to subdivide?

and will I be able to build 2 units on a block that is 50' x 150' in size

any help will be appreciated,