Warning: TLDR;
I'm rambling about which cards I signed up for to get 6 people to Barcelona and the difficulties of a newb navigating miles databases.
Two months ago -- pretty much to the day -- I found this thread. I was facing the task of getting my family of 6 to Barcelona for the cheapest fare possible (since I was spending my parents' money). I was looking at rock bottom prices of about $415 per person. But you guys got me thinking.
I searched for flights from the East Coast to Barcelona (I was willing to take any airport from Boston down to DC), and found consistent reward availability on a United direct flight from Newark to Barcelona. Realizing that I could accommodate my whole party in economy very easily, I set my sights on business class. The United flight would cost 57,500 miles per seat, but partner business saver awards were pricing at 70,000 miles, so I wanted to be sure I had enough of a cushion that I could pay the higher fare if necessary. Turns out it was good that I did. Here's how it worked out:
Each of the 4 adults applied for a United Visa card. With $1,000 spend and a charge by the authorized user, that gave each adult ~36,000 miles. That's 4 cards worth of spend: 2 cards spend was accomplished by each household prepaying $1000 worth of propane (that's about 2 months' worth of heating here in New England). I completed my other spend by paying some work-reimbursed expenses and buying $750 worth of grocery gift cards for spending that I had already budgeted. My dad completed their second spend with household expenses.
To get us up to 57,500 each, my mom and I applied for the Chase Sapphire Preferred. The 55,000 sign-up bonus, with the 4,000 points generated by the spend itself, got my parents up to 65,500 miles each: enough for the United flight. My dad has had a Freedom card for a long while now, and had 12,000 points sitting in that account. So they were set even if I had to go up to 70k in airfare.
It was a bit more complicated for us. Even with the bonus miles I got paying $4,000 down on the cruise to meet my CSP spend, we were just covering my and my husband's airfare -- still two kids to consider! The timing on this is funny, because the night I applied for my CSP I called Chase recon, and they explained how busy they were because of this big new card that had just debuted that day: the Chase Sapphire Reserve. WOOHOO!! I immediately had my husband apply, met the spend by paying off another $4,000 of the cruise and got 3x points for that.
The final bit was that we were scheduled to visit my in-laws in Japan at the end of September. My DH had booked us on ANA, and so I was able to have our miles credited to our United Miles Plus accounts. The only annoyance there was that the kids ended up with their own mileage accounts. No big deal, right? Chase lets you transfer points to household members, right?
The night before the reward tickets became available on United's site and the night before the very last of our UR points posted with our credit card statements (talk about nerve-wracking), I tested out how to transfer UR points to my children's Miles Plus accounts... except... I now find out that you can only transfer to a person who is in your household AND an authorized user on the account. Oh, and you can only transfer to ONE authorized user, chosen for the entire year. EEEEEP. I quickly added my daughter to my CSP account, but I'm NOT about to pay $75 to add my son to my DH's Reserve card. It's 6pm -- only 7 hours before the tickets will become available -- and I'm informing my DH that he has to apply for a CSP *right now* and add our son as an AU. LOL Poor man was eating dinner and talking to recon because I typo'd our income on the application. The awesome news is that his CSP was approved and immediately appeared on the Chase website, so I was able to use it to transfer points to my son's Miles Plus account that night. WHEW!
After that, it was pretty simple. United totally up-ended availability on their direct to Barcelona flights, so I had to get creative to find room for all 6 of us in business class on one flight. Still, a 9.5 hour stop-over in Vienna means Schonbrunn Palace and time for a nice lunch and a peek at the downtown area. There was a bit of a snafu with the short hop flight from Vienna to Barcelona: when I started it showed availability for 6 people, but, after booking my children's flights, that flight totally disappeared from United's system. I've talked to 4 different agents and none of them could do anything, even though the flight is there with oodles of reward seats the day before and the day after. Ah well: the UR points from my DH's emergency CSP will more than cover purchasing those tickets separately.
Aaaaand, in the meantime, I got awfully jealous of my husband's CSR, so I had to get one for myself.
Turns out the sign up bonus is just what I need to put us up for 2 nights in a lovely hotel in the Gothic Quarter of Barcelona.
Not sure how it decided to cover the charges in reverse order lol. Love that the DVC rental coded as travel 
I have the CSP, and what I have coded as travel is plane tickets, bus tickets, hotels, subway and parking. One month, I had about $30 that I couldn't figure out what was coded, but I can't think of any "everyday" stuff coded as travel. Tires - no, oil changes - no, gas - no.
