can best offer be accepted without my knowledge

[ambience-now]

If i have no notification, can the item i am selling automatically accept  best offer.without my input

[digital*ghost]

Yes, if the auto-accept option has been selected. When you list an item with the Best Offer feature, you can opt to manually review all offers, or automatically accept or decline offers above or below a specific amount (you can't set a listing to automatically accept an offer without specifying a minimum amount, eg say you have an item for $50 and set it to accept any offer over $45 automatically).

If the auto-accept option has not been selected, any offers will expire after 48 hours.

[*sparklz*]

Yes if you have entered an amount to auto accept.

When you do buy now with best offer and do not tick the box and enter prices to auto accept or decline then you will be messages via ebay with any offers submitted and from there you can accept, decline or counter offer.