Re: While booking an international air-travel trip..
For me, I have travelled for vacationing so I guess that effects your priorities. This is about recent trip to Malayasia:
-FARES:
cheap fare ofcourse ; book through travel agent for tickets AFTER my homework on airlines, ( I dont mind connected flights and would rather prefer to get a transit visa to stay a day or two during the connected flights if possible
) because living here in Pakistan,everyone tries to rip you off if you have no idea on pricing and options. matrix.itasoftware.com has been really helpful for my recent trip to Malaysia because due to the political scenario in islamabad last month, our passports were stuck in the embassy in Islamabad for 2 weeks and we had to change our bookings twice for flights and a hotel. Had I purchased tickets online, change of dates would have been a mess so going via travel agent was a blessing since he took care of it and I didnt have to pay anything for the change. ( I even changed the dates of getting back home after half of the trip was done because we found out husband and kids have 3-4 days off from work/school here somehow so we requested the agent to forward the bookings
and he did that without any additional costs as well )
For Langkawi we took and ATR (Malindo Airline) instead of Air Asia because I heard shopping is cheapppp in Langkawi and Air Asia charges crazy prices for luggage while Malindo has first 15kg free on each ticket. We left some of our luggage with the pakistani guy so we were pretty easy with that.
I am a serviced apartment person rather than a hotel one. I find it easy and convenient to use a stove and a microwave oven to reheat lunch leftovers for dinner and get our breakfast done in the room rather than rushing out to restaurants thrice a day for meals. Plus it is easier with kids since there are usually 2 rooms so we can relax better.
I got hotel bookings done via booking.com (free cancellation wali) but as I said earlier, we had to change dates so I cancelled them all except the one in Kuala Lumpur because we wanted a place to stay as soon as we land there rather than finding ourselves a place. It was an apartment hotel (Berjaya Times Square) I booked 2 nights initially online and then we looked around and found a Pakistani (Lahori :D) man who had apartments on higher floors in the same building for half the price so we moved there after 2 nights. We were flexible with our plans since we didnt have bookings in other places so we changed the apartments thrice in 8 days as per availability and while it would sound cumbersome to some, I didnt mind that. We enjoyed all the views
and being on 42nd floor, didnt even opt to get tickets for the sky bridge since it is on the 43rd floor at the twin towers and was right infront of our window in the room :).
Anyway, I got further booking done for legoland via a local tour (My local tours) operator we came across while roaming around. They gave us best ever prices, way cheaper than booking online for the legoland entry tickets (135RM for a day instead of 185RM if purchased directly from legoland counter) , and the return airfare to Langkawi. They also helped us book a night near legoland for minimal price. For Langkawi, we rented a car for 5 days at the airport and went to check out shortlisted hotels ourselves. Hated the one I loved online lol so we found a 2 bedroom apartment for first 3 days in one part of the island and then a 1 bedroom resort apartment in the other end of it..enjoyed the sunrise for 3 days and sunsets of next two right in the room 
-Roaming around :
I try to save as much as possible here as well
without missing any important attraction at a given city. We were easy on taking buses and trains most of the times (had to work a lot to know about the routes and options pre hand though) because taxi walay just rip you off as a tourist. Loads of haggle and lots of walking but saved a LOT to spend on other stuff which were not in my list initially because of budget constraint. Same for the theme park tickets and entry tickets to other places;planned ahead and bought family tickets via local tour agents.
-Shopping/gifts:
Bought loads of chocolates and some perfumes from Langkawi ONLY because it was a duty free island as I read online and observed that the prices were veryyyyy good as compared to other places. Rest , I tried to hold myself back as much as possible and spent in adding more places to see in the country with the saved money.
oops, sorry for the long post
I dont even know if that all was relevant to the thread @SID_NY