I have been looking for a simple cost efficient way of installing blinds on some of the bedroom windows. The windows are nearly 3 metres above the ground and 2.1 metres wide. I did not want a manual method of using long cords hanging down to the floor level because of the child safety risk.
The blinds only purpose is to block out summer light at night. There are solutions for the outside which are the norm across Europe but these I deem too complex. These same units have multiple purposes such as security, provide darkness and reducing solar gain. The simplest to maintain I feel are shown below from one of the following suppliers . The units will not be used every day (unnecessary in the winter) so they should be reliable. The prices start at around 80 Euro.
For the above I have installed cables to supply power rather than use the solar option. These cables can then be fed from one central point with the appropriate voltage from say a battery charged by solar. I also installed the wiring so that a manual switch can be installed rather than using a mobile phone.
What will be important for the above is to find a blind mechanism that is smooth and reliable. Some of the online prices for these appear to be around €90 for 2.1 meter wide and 1 meter long.
If one wants to go the traditional way then the video below may be helpful. When I priced internal motorised blinds in Ireland they were costing around €400 each.