There are three main concepts for changing the motors that are all on YouTube. Solder the new motors straight to the board as the originals are, cut the wires pretty close to the motor and add (solder) a permanent connector for easy future changes, and the easiest no solder method of cutting the wires pretty close to the motor and simply hand twisting the new motor wires together. All three methods have pluses and minuses that you can deduce and decide what is best for you. I personally think it is very easy and quick to install new motors but it will depend on your abilities and experience.
I estimate 30 to 80 flight hours until the motors need changing depending on when, where, and how used. These types of small brushed motors have the potential to be instantly damaged with any type of crash or bump that stops the motor from spinning for even a nano second. So to answer your question at least for my heavy and risky flying habits of using the drone as a scout for my adventures, I will probably change out the motors four to eight times until I will probably need a totally new
Tello or the
Tello 2 has came out.
These are the ones I personally like and it is 4 motors for $12.
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