When you do DIY remember that DIY also stands for “Don’t Injure Yourself”. A fall from a ladder, or an accident with a powertool could end up costing you a lot more than money.
Do DIY...
Painting – interior and exterior.
It’s important to know what you’re doing. Don’t rush preparation and be careful up ladders, on scaffolding and on roofs. If you are not certain about your colour scheme it is worth painting a section of wall to help visualize what it will look like. Bear in mind that a big painting firm will be able to buy paint cheaper than you can. Don’t use cheap paint – it’s cheap because it’s not as good as the top brands. Remember to factor in the cost of scaffolding.Landscaping. While a landscape designer might seem like a luxury, a good one will add huge value to your home. Think about it – if you’re planting trees that are going to take ten years or more to reach maturity, you should be absolutely sure that you’re planting the right ones! If your budget is tight, consider getting a landscaper to design a plan - and do the grunt work yourself!
Laying lino or timber veneer flooring is fairly straightforward, but do your homework and make sure you have the right gear.
Putting hardware on doors is do-able for the average home handyperson.
Don’t DIY...
Gib stopping – looks easy, but you don’t want to feel annoyed every time the light catches the irregularities in your walls.
Tiling – again you can do it, but if you get it wrong it’s costly to undo to get right!
from:http://www.lookhome.com.au/GetIntoIt/GetPractical/TheBuildingProcess/BuildingBudgets.htm