No where near 200-250. More like 100-150k. For 200-250 your talking knock down/rebuild.
Kitchen/Bathroom - $40k
Paint inside/out - $40k
Floors - $10k
Structural modifications - $20k
Landscape front/back - 10k
Other bits - 10k
= 130k
130k + 8-10% prelims + 8-10% builders margin = 150k - 157k (if you're doing it with a builder and not just organising all trades yourself). Also assuming you didn't get an architect/engineer in for design fees. Also unsure if there'd need to be a DA submitted for this level of works or anything else to go to council.
40k for all new tiling (floor to ceiling wall tiles in both), fixtures and fittings (baths, WC, vanities, frameless shower screen, tap sets, etc. etc.), joinery, plumbing/gas, electricity, appliances (oven, stove, rangehood, new HWU) to two new bathrooms and one new kitchen and relocation of laundry? Keeping in mind that needs to be re-routed through existing stuff so possibly chased in to walls? Also potentially need to put in new sewer lines?
I'd think closer to 60-70k at least once you account for moving of services. Could be wrong though.
I also thought it was rendered on the outside looking on my little screen, if not you can probably knock 15k off down to 185-235.
Floors allow for tearing up of old boards, sub-structure, floorboards & carpet on top of floorboards upstairs (and I presume to stairs)? Again I think you are stretching for $10k
Demo costs of existing items? Bins if you're doing it yourself?
New bifolds including structural changes (knock out bricks, supply/install new steel beam)
250k is a stretch and only if you're going with good trades, good finishes and going to live in it (the kind of work I normally price)
This all depends on who you are and what your skills are. If you flip houses for a living, have a good team of tradespeople and a mate who can do some drafting, yeah you're right I think $150k is achievable.
Doing it "hands-off" though? $200k any day of the week.