Items dont get lost if you use registered post (tracking number starting with R e.g. RS123456789CN).
Companies like yanwen and even china post small packet have high rate of not reaching your home.
Tax depends on item and mood of customs people.
Most small items are untaxed.
In my experience.
On ordering raspberry pie 60 rs tax.
On ordering handbag, wallet, memory card, etc. no tax.
Got taxed between 1000-1500 (dont remember exact amount it was customs tax and 2-3 other charges) for a CCTV cam.
Ordered LED lights and projectors for car and no tax on them.