The UA Card is 2k/3 months spend. You could get that and end up with 57K miles (50K + 5K authorized user + 2K spend). It will cost 80K miles roundtrip per person to fly United to Maui. You would both need to get the UA Card and you would have more than enough for 1 way for both. If you both get the CITI AA card (3k/3 month spend) you would have more than enough for 1 way for both. Get the Hyatt Card down the line as you get 2 free rooms at any Hyatt, the CITI HHonors Reserve card will get you 2 free nights at Hilton, Fairmont credit card will get you 2 free nights at any Fairmont. All three hotel chains have hotels in Maui. If you both signed up for those 5 cards and complete the spend before your trip you would have 114K united miles (57K each), 106K AA Miles (53K each), and 12 nights hotels in Maui (4 each x 3 cards). The only problem is 3 out of 5 of those cards are Chase. If you space it out far enough between Chase applications you might be fine.