Originally Posted by
iwillflytheworld
United doesn't sell tickets with open returns using this terminology...
Actually, they do -- bereavement fares are one popular example (the return is shown as 'OPEN.')
Many other fares allow open returns as well, but they're usually refundable tickets and UA encourages you to book a specific return date & change it as needed.
If he's planning to change the return date at most once, the optimal solution would be to buy a cheap fare which allows changes for a fee...
I agree this is probably the best solution, but he needs to check the fare rules with his travel (or booking) agent -- he needs a tariff who's maximum stay covers his expected length of travel. If he buys one of those cheap fares floating out there that allow a maximum 30-day stay, he'll likely pay more in upgrading to a higher fare (permitting a longer length of stay) + the change fee at a later date than he would purchasing it up front.