To be fair, research and development for a capability on ones
own requires time and effort which translates to increased cost.
Many times, there are trials and errors which also increases cost.
After all Malaysia did not have the capability to produced armoured
vehicles previously so the ability to do so is something new to
them.
They can get some other company to cooperate with them much like
what Singapore did when we develop the Delta frigates. But they
wish to do it alone, maybe because of national pride. Another way
is to just buy them from overseas. There are many such armoured
vehicles in the market now and simply just buying them cost much
lesser.
My personal opinion is that there may be corruption as this have
happened before with other government projects as well. And
choosing to go alone may mean that all the money can go into the
hands of local people. But of course we will never know the
details. 
