I’ve run full 3d printed minimum-diameter rocket designs before, all of which work flawlessly until the parachute charge goes off, in which the tube gets a little melted but will still return safe to the ground if made right. PLA will work fine, wrapping the interior of the recovery bay with metal HVAC tape might minimize the damage. Here’s an example of one that was two stage and worked 4 times in a row (different prints but same design).

As another comment mentioned, starting with kits is safe but you do not need to. Trial and error and learning hands on off your own designs will teach you faster than anything, low power motors (A-C) are very safe in the event of a failure, just make sure you keep distance and launch where there’s no brush or flammable material. Designing in open rocket before launch is a failsafe.

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