When looking at a home, certain things should give off a warning to a home buyer.
The first photo is of the gap between the pathway and the house, showing the pathway has moved 100mm away from the house. This is probably due to poor site preparation on reactive soil or a retainer wall not adequately supporting the soil around the house. As this house has been built on a strip footing, this is a problem.
The second photo is taken from the roof looking at the rear verandah that has had some very DIY roofing added. The roof sheeting is obviously not adequately supported or attached and is dangerous.
The roof restoration was so poorly done, that tile edges were not painted, sealant gaps not filled and cracked tiles just painted over. I would assume that they were not adequately cleaned either, so the roof paint is likely to blister and peel.
Newly replaced timbers in the under floor area and roof space can represent termite damaged timber has been replaced or in this case, the DIY effort was to assist in replacing broken timbers. The roof collar tie was not level, so definitely  DIY, the original ones may have been broken by some one in the ceiling space placing a load on it. The flooring timber beam shown has been inadequately strutted directly to the ground. This is making a bridge for termite attack directly to the flooring, so definitely a DIY effort. The support is just resting on a brick off cut, so not actually supporting anything. This is nothing a tradesman would do.
This house door frame have had the door re hung, but the hinges are poorly fitted and the striker plate missing from another door frame.This is a minor issue, but shows the amount of care given to the home renovation to sell.
The next photo is of the driveway sinking 120mm down from the carport concrete floor level. A  car could not drive over this step up. The cause is the failure of a retaining wall and subsequent sinking of the soil due to poor sub soil preparation for reactive soil. The soil has also been affected by storm water flow due to miss alignment of the storm water down pipe, allowing for water to enter the sub floor area and wash out the ground under the drive way causing the sinking.
This same house has leaking bathroom issues with drumming floor tiling caused by the movement of the sub floor area flexing the bathroom floors. Also salt damp issues as shown in the photos as well as minor cracking to the brick work mortar and weathering and fretting of the mortar between the bricks due to poor mortar mixing by the brick layer.
I can not show too many identifiable photos for legal reasons as this home is still on the market and the vendor will find a buyer eventually, so buyer beware.

​Converting a carport or garage can be an economical way of gaining extra room in your home. From my perspective however there are many issues this can create.
The concrete floor will not be moisture proof and damp issues will occur if another floor is not correctly installed.
You loose your car parking space, which can increase your car insurance premiums, as well as loose valuable storage areas.
The ceiling lining may now be an asbestos sheet, above where you have a bed positioned as any house built prior to 1985 would have asbestos sheeting used for the carport ceiling lining.
I do find a lot of wall moisture issues, mold issues etc in any converted carport wall. This then becomes a possible termite attractive zone, as the cladding is often over carport posts, that have inadequate or preventative pest treatment applied. The wall framework is often set down against the pathway or worse the driveway edge at ground level. This can enable moisture to wick up inside the framework providing the damp timber that attracts termites. 

​Winter and wet weather issues on a roof can be expensive to rectify especially if left not repaired.
Checking roof pipe penetrations and the lead flashing for cracking can often expose many areas of concern to be inspected inside the ceiling cavity. This roof for example, was be letting in enough water to cause serious damage wood rot of the ridge beam and rust out the nails it was supported to. The issue here was caused by cracked tiles.

Pipe penetration and lead flashing are the main cause of leaking into most roof cavities, closely followed by broken or damaged tiling and missing pointing

​A recently renovated bathroom may look great, but if it was a DIY project by the Vendor, it's probably not to code and you will be stuck with seriously expensive issues. The shower in this photo actually had falls away from the drain and out under the bathroom door into the hallway. If they could not get the falls correct, what hope did they have of doing the waterproofing correctly. The failed water proofing will result in the entire bathroom requiring to be stripped back to bare walls, as leaking bathrooms can result in wood rot, mould and termite activity like shown in the photos below. The 3 photos below are from the same home, showing the termite damaged floor joists and bearers that the newly DIY renovated bathroom was hiding. Firstly the sub floor should have been replaced prior to the renovations. The power point should not be recessed behind the tiles, as this produces a moisture issue and makes fitting the snap on cover almost impossible to finish off nicely. Lastly the floor falls should be 1cm over 80cm, towards the drain in the shower area, it was actually raised and the highest point of the bathroom. To rectify the floor issue would require the entire floor to be removed, as would the issue with the termite damaged timber that requires replacement. 

​Previous pest inspections are an important factor when looking at a house to buy. Having received my statement of attainment for inspecting for and the reporting on timber pests, also the control of timber pests, I understand the processes that prior pest operators have applied.
Treating areas with pesticides, considering some of the older treatments were quite poisonous, it is important to understand why they were used as well as where.  Sometimes however the spray operator may have caused structural damage to the house, to make his job easier.
The home owner is never likely to crawl under the house, so short cuts are made to gain access and unless you employ a diligent house inspector, you too would never know. Until you suddenly have a structural failure of the flooring of the house you purchased.