International Trade Finance

Fashion-4-U is a rapidly growing manufacturer and exporter of ethically sourced fast faction. it has recently obtained two new retail chain customers in Mexico City, Mexico. Both have agreed to use letter's of credit to finance the transaction. the first customer has selected and advising bank that the exporter is not comfortable with. the second customer has chosen an issuing bank that is not financially stable.fashion-4-u would like maximum flexibility to deal with other banks and more security that it will be paid. as an exporter, what agreements or changes to the letter of credit should fashion-4-u request?