Option buyers don't have to pay a deposit. Option buyers only pay the premium of the option contract, and they also need to pay a certain fee. Then basically they don't need any other fees. Option buyers can wait for the option price to rise to gain income. If the option price falls, the biggest loss is limited to buying the right part of the option contract.

What is the margin for the option?

Because the seller's income is limited and the risk is high, in order to prevent the seller from defaulting, the exchange or settlement company will charge the seller a deposit according to a certain proportion of the value of the underlying assets. The buyer's risk is limited to paying commission, so no deposit is needed.