If you want a mavic, just buy a mavic, building something with this level quality / reliability is not worth the effort.
The advantage to building your own is that you get a different type of quad -- a racing quad which feels more like flying a porsche (feels like a race car) than an mini-van (e.g. mavic, reliable but super fun to fly).
If you want to build a racer, rctimer has some of the best kits (high quality parts, well thought out design). Here's an old build guide from my blog, you would want to get a newer kit with an omnibus-based flight controller, but the idea is the same: https://nathan.vertile.com/blog/2016/04/24/rctimer-u210-mini...
The advantage to building your own is that you get a different type of quad -- a racing quad which feels more like flying a porsche (feels like a race car) than an mini-van (e.g. mavic, reliable but super fun to fly).
If you want to build a racer, rctimer has some of the best kits (high quality parts, well thought out design). Here's an old build guide from my blog, you would want to get a newer kit with an omnibus-based flight controller, but the idea is the same: https://nathan.vertile.com/blog/2016/04/24/rctimer-u210-mini...
Also, if you're just learning to fly, you probably want to learn acro/rate mode (which is full manual mode) on something smaller first, like this maybe: https://nathan.vertile.com/blog/2017/03/31/betaflight-micro-...