Construction equipment and materials happen to be quite expensive so not everyone would be in a position to invest in everything related to it unless they have the required resources and unless that is what they do on a full time basis.
Scaffolding towers and other construction equipment would be examples of those equipment that you would prefer renting if you only have occasional uses for them. If however you make daily use of scaffolding towers and related construction equipment then you may find it to be a better option for you to invest in them and purchase them instead of renting them as it may not be financially viable for you to go through rental companies to meet such requirements of yours.
If you have an urgent need for a scaffolding tower and if you do not have the budget to purchase a new one nor do you have an idea of wanting to use it on more than a single project, then all you will have to do is look for all online scaffolding rental ads which would also depend upon what area you may be from.
There are some reliable ‘scaffolding rental’ (also known as ‘steigers huren’ in Dutch) companies that you could approach for help as that is what they specialize in and they know exactly what you may have a requirement for thereby allowing you to meet all of your requirements effectively.