One way of reducing cost is chop/split the grass patch into smaller patches, and plant each smaller patch 3 inches from one another, and let them grow, spread and cover the garden. With that, you need only 500 sf of grass. But becareful of weeds. One way of preventing weeds, is to put 3-4 layer of old newspaper on top of your soil, get a small truck load of 'yellow soil (those without the weed seeds)' and cover the newspaper and plant your new grass on top. You will have less weeding to do in future.

Grass Rm2psf = u need maybe 1000 for 500sf
Upah tanam = free, do it yourself, that's the fun of having garden.
Soil= make sure it's weed seed-free soil, the yellow one deep down.
Baja= no need baja, i never used baja. Be environmentally friendly, collect your overnight urine in a potty, mix 1 part urine per 100 part water and just pour on the grass before you water the grass. Afterall grass being leafy needs all the nitrogen from your urine.
Racun rampai= do it about 2-3 weeks before planting otherwise your grass will die.
Sprinklers= much needed tool
Drain cover and sewerage cover = 1 stainless steel sewerage cover around RM1000. Be innovative, just a piece of granite slab as cover, reinforce the bottom with cement + wire mesh. Cheaper but Probably need expert help with this.
Pokok paga= Much needed
Batu Sungai= Can get from Kampung. Cheaper but ILLEGAL!

By the way, if you are a pilot, 3300 for a garden is nothing..