Sale Ezy's 'Tech building Trust' series provides regular reviews of apps and businesses that support the real estate industry and help build trust between agents, buyers and sellers.

So, you're thinking of selling? But when you take the emotion out of it; the memories, the personal touches that you love, the neighbourhood you intimately know, how much is your home really worth?

Not selling? Buying? Do you know what you want, where and how much it should really be worth? Are you sure your offer is reasonable, but you aren't going to pay too much to secure that property you've had your eye on?

If you've watched TV in the last... ever... you will have seen the many ads offering online, immediate property appraisals. Likewise, if you've wandered onto realestate.com.au or domain and Google has magically picked up you are interested in buying or selling, Facebook is now probably battering you with ads encouraging you to get your free property report.

The question is, how much can we really trust these property appraisals?

Why do online property reports and appraisals exist?

If we're being honest, online property reports exist for two reasons:

1) They are a FANTASTIC marketing tool. They are a 'free' value-add a company gives you so they can either collect your details, direct you to a page and place a cookie, or just help you remember their brand, so they can advertise to you later.

Companies from real estate agencies, through to banks, mortgage brokers and property advertising display sites all offer reports varying in detail.

2) They meet a consumer need. Despite relatively new and stringent underquoting laws across many states in Australia, consumers have an innate distrust of many real estate agents.

Buyers are tired of searching for properties and seeing ads, running around and turning up for opens, registering and attending auctions, only to see the first bid is tens of thousands (if not hundreds of thousands) higher than their bidding ceiling. They feel their time has been wasted and agents have lied to them.

Underquoting laws go a long way towards fixing this problem, with many agents now restricted to advertising prices using very specific wording, providing one asking price or a top and bottom figure limited to a 10 percent range.

They also have strict rules they must adhere to when recording requests for price and the response they provide, and adjusting the advertised price when offers are rejected.

Free property reports increase that trust and help buyers feel more informed and equipped by giving them some reinforcement.

They often also provide a range. If that range matches what the agent has told them, the buyer can feel comfortable packing up the car and heading to auction on a Saturday morning!

What do property reports tell you?

Property reports vary in their detail and in the information they provide.

At the less-detailed end of the scale, you can type in the address of a property (and usually your contact details!) and you will see an estimated price range appear on screen, perhaps with some support for how the figures were formulated.

At the other end of the scale, you not only receive that price range, you also receive a complete justification for where the range comes from. It might include details about the property, its sales and/or rental history, similar properties for comparison in the area, and a myriad of information about the suburb and neighbourhood.

Regardless of the validity of the price, the information about the history of the property, comparisons and information about the area are incredibly valuable to anyone looking to purchase.

How reliable are property reports?

This question again depends on the property report and the company producing it. Many of the reports get their data from the same places, reputable data outlets like RP Data that collect a vast range of information about properties and the market in general.

What's important to remember is that the range is calculated using an algorithm that draws on available data -- so what it can't possibly consider are factors for which it cannot or does not have data.

These factors might usually cover things that a computer doesn't really keep a track of: upgrades made to the home, the condition of the home or yard, changes to the neighbouring properties or within the neighbourhood. These factors can have a HUGE impact on price.

For example, a three-bedroom property in good condition, with new kitchens and bathrooms and hardwood floors will likely be valued higher than a three bedroom home in the exact same location that has outdated bathrooms and kitchen, old carpet and falling down fences.

When reviewing the property report you receive, don't be under the impression given to you by the ads, that you can waltz in and tell the agent how much the property is worth, because likely, their appraisal takes into consideration all the available data and more, and yours does not.

What's the verdict?

Property reports are absolutely a valuable and useful tool in your property search or even if you are considering selling your home. They can be a great tool to help inform your path to further research and a better understanding of the property, its history and the area.

In saying this, don't take the price range as gospel, because the report likely hasn't considered all the factors. Take it for what it is, a guide.

If you're selling and want to know the real value of your property, or you're buying and you're not sure about the price being asked by the real estate agent, invest a little cash and have a licensed valuer do your homework for you -- you never know, they could make or save you thousands!