I think the D800 will be around SGD4000 and above. If it has higher megapixel, be prepared to buy a real good and expensive FX lens, like the 24mm f1.4G, 14-24mm f2.8, 70-200 VRII, 200mm f2, etc. Any crappy lens will defeat the purpose of getting such expensive D800.
And the current D700 is already good enough for any assignments, not to say for hobby only. You can grab it at SGD2600 and below in Malaysia and B&S section now. It's real cheap for such high performance DSLR.