code: async function prepareTxParams (txType, { senderId, nonce: n, ttl: t, fee: f, gas, absoluteTtl }) {
    const nonce = await this.getAccountNonce(senderId, n)
    const ttl = await (calculateTtl.bind(this)(t, !absoluteTtl))
    const fee = calculateFee(f, txType, { showWarning: this.showWarning, gas, params: R.merge(R.last(arguments), { nonce, ttl }) })
    return { fee, ttl, nonce }
  }
docs: Calculate fee, get absolute ttl (ttl + height), get account nonce
  
  @param {String} txType Type of transaction
  @param {Object} params Object which contains all tx data
  @return {Object} { ttl, nonce, fee } Object with account nonce, absolute ttl and transaction fee