To demolish or not

Hey all,

I have a 100 year old skillion roof weatherboard shed and dunny right on my boundary and I am next to parkland. I would like to replace this with a double garage (wb and gable iron roof) however planners tell me I have to set the lot back from the boundary if I build new. If I do that, my garage becomes single as I dont have the metre-odd to spare.
Seems bloody beuarucratic given the park is next door, ie no fire hazards etc
I am now thinking of keeping the original shed wall on the boundary and with some upgrading to frame etc knock up the garage without the council knowing the difference.
I reckon I may have to put a new foundation under the old wall though.
What do you reckon??

Will they let you build on the boundary with the "necessary" fire proof wall and the like.

There is much being built on the boundary in this neck of the woods, but one of the restrictions is no more than 10 mtr can be on the boundary, also it must comply to the 60/60/60 fire rating.

Yet you can keep a wood pile between a wooden fence and your house or build a shed there so long as it is less than 10 sq mtr, then fill it with paint, engine oil, a 9 kg gas bottle or 2 and 10 or 20 ltr of mower fuel, makes no sense to me.