Drone Deprecation in an LLC

[MotoSavy]

Please be gentle and don't beat me up for asking the question. If you don't know or want to answer, please disregard and don't insult me or tell me to consult an accountant.

I'm in the process of starting a drone business. I know that you can depreciate the drones several different ways.

By searching the internet I found that businesses can depreciate assets these different methods:

straight-line basis
declining balance
double declining
units of production
sum-of-the-years’ digits

For those in business, what method do you use and what useful service life do you use for your drones? Please don't take crashes into consideration when depreciating an asset. Repairs are tracked differently.

As technology evolves, we may want to upgrade our drones to newer models before their useful life expires.

So on average what do most in business owner use as a service life for their drones?

I'm thinking of using about three years of service life for a drone. Does that seem adequate? I think that after three years, I would want to get new drones with enhanced technologies.