When buying a new home the normal precedure is to have the home inspected. One precedure that is pretty much over looked is the landscape inspection.
As I drive around and see homes for sale, I have the urge so many times to leap from the car and red tag the yard or put a warning sign out saying 'buyer beware'. Some things I see are large dead trees that in winter the unsuspecting buyer might think are dormant and are really dead. Having large dead trees cut down and removed can cost into the thousands. Another problem is lawns infected in fungus. Fungus is a costly problem to inherit.
In new construction, I am horrified with the placement of plants. People calling themselves landscapers because they can dig holes plant incorrect plants or plants in the wrong place. For example, a home with front columns 2 feet wide will have a Yew in front. Well, Japenese Yews can grow 15' to 20' tall and 6' to 8' wide. While it looks great first planted from the 5 gallon bucket, in a few years you will not be able to see or get through to your front door. Many people will say they will keep it trimmed. Trimming a plant to 2' that wants to get that large will stress the plant causing it to be prone to plant disease and insects. I cannot tell you how many landscape calls we get to redo intalled landscapes that have failed due to poor planning and lack of knowledge. Why pay for something twice that you already paid for.
Another area to check is to run the sprinkler system through a full cycle. Be sure to ask for a zone map and if the operators manual is available.
When buying a home do a little research on the plants that are planted. If you do not know the names, ask for list from the landscaper or take pictures and take them to a qualified person to identify them for you. On your trees, if in doubt call a certified arborist. If there are problems it is better to identify them before you sign on the bottom line.
Who knows, you might can negoiate a better price. Newly planted plants are pretty easy to move around to a better suited spot and this is something that perhaps you can do yourself or have the owner have done before buying.