One of the easiest ways and economical ways to boost energy efficiency and safety is tinting home windows from the inside. This can be done without replacing the windows. Generally, all residential windows are made up of self- adhesive polyester or lightweight.

Things that are crucial for home window tinting:

• Different types of window film offer several benefits-
o Solar- The option is recommended if you are looking for improving energy efficiency. It is thinner than a security film but thicker than a decorative film. The solar film is known to absorb 99 percent of UV rays.
o Decorative- It is one of the thinnest types of window film. It reflects minimal heat, and the primary purpose is to add beauty to a room.
• Not all types of window films are compatible with all window glass- Different types of windows absorb different degrees of heat. Mostly all security and decorative films help in blocking minimal heat and thus not placing much thermal stress on the windows.
• Installing commercial window tinting can void your window warranty- Ideally, the majority of the homeowners report window damage to their manufacturer only to know that they invalidated their guarantee by applying window film to the glass panes. Thus it would be best if you never began tinting your house without having a word with your manufacturer.
• It's easy to install the tints- If you are planning to install the window yourself, then it is advised that you wipe them down using a tint free cloth with one teaspoon of no-tears baby shampoo.

Window films are great choices when you want privacy at a low cost. These are great if you want to block unwanted UV radiation. Moreover window films are great way to decorate your interior. I have found a roundup post on privacy window films here, read and enjoy.
Source: https://helloportable.com/best-window-film-for-day-and-night-privacy/