Renovating a basement in any property is unlikely to lose you money. This is simply because you have, if professionally done, finished the basement to provide additional living space. However, a thorny question does arise because it does mean what type of basement. There are basically three types of basements that we have to consider.
There is strangely the walk-out basement which is not really sub-terrain at all. It is basically at ground level of a large house that has natural level, average sized windows, and typically atrium doors. This of course makes this type of basement apartment very valuable so tops the rates for value adds to your property.
The next type of basement is designed around a partial sub-terrain basement and this usually comes about when a building is built on sloping terrain such as a hill. In this case the property will not have the facility to have full sized windows or doors instead they will need to use smaller and light restricting windows. This makes this type of basement less attractive.
Finally we have the fully sub-terrain basement, which is the most unattractive of them all as there is no natural light from windows and no access doors to the exterior. It might not sound like much but humans do like to see the natural light through a window no matter how small. Having no sense of natural light can be disturbing for guests if they are asked to sleep in a basement bedroom and they could find that experience strange.
But of course there are other considerations especially to the quality of the workmanship and the designers. There is also how you go about the way you transform your basement. For example a self-contained apartment might be a huge selling point for one customer as they could offset their mortgage payments with the additional rent but for others it might be seen as an unnecessary burden. We also have to consider that a basement set up as an on suite guest room might also have limited appeal. But of course the very opposite could be true and someone views your house with exactly the same taste as you so sees it as perfect.
The core features that most people seem to want and are then willing to pay for are quite basic. They will need plenty of lighting and head space at least 8 feet. Anything less can cause people to get claustrophobic especially if there is no natural light. After all they need to be comfortable in that living space and no matter what purpose you were using it for they can change it but not if they are not comfortable in that space.
What is important to realize is that valuating a house with a basement is not clear cut. The added footage of living space cannot be included in the house valuation as above ground living space is valued far higher than below ground living space. However, that added livingspace will stillincrease the value of your home.