I guess I more or less agree with flyboy.
1) How many kites should I buy initially? (I have read that most travel bags can hold 2 kites, 1 board, lines, pump, etc.)
I have no issue fitting 3 kites, a board, pump, harness and bar in one of these "golf bags".
I got 4 kites (7, 9, 12 and 17), but I have never used the 7 (I'm 225lbs). 7, 9 and 12 covers most conditions for most people. And they generally speaking overlap nicely. When the wind is too strong for the 12 then the 9 works etc. 9 and 12 is usually a very good starting point. Then you can go 15 or 17 later if you want to kite in light wind or 7 if you end up travelling to Brazil. Or you might go for example 8 - 11 - 15. Covering all but the extremes in both ends with 3 instead of 4 kites. Not all that easy that decision as the first kite you buy will influence how you can best structure your quiver later.
All this based on TT. If you end up with for example a surfboard then smaller kites are more relevant as you need less power.
2) How many boards should I buy?
I have never had more than one at any given time. A #%"¤#"¤ to travel with more than one TT.
Don't want to overcomplicate things, but there is a relationship between number of boards and kites. On a huge board you might use a 12 instead of a 17 when the wind is light, but you don't want to use that huge board when the wind is good. Personally I prefer having one board and more kites, but that is a personal preference that might vary from person to person.
Personally I would also recommend to buy a fairly big board (not light wind big, but 141x42 or something - remember width is important for the overall area). So much easier to progress. Boards are also from my experience easy to sell if you want to replace it later with something smaller.
3) Will I outgrow my gear fast as my skills increase?
Unless you are going to kite regularly several times a week I would say no. As an example Ozone Catalyst is known to be a "beginner friendly" kite, but I have seen people do tricks and jumps with that kite 99% of all kiters are incapable of performing. Doesn't mean they wouldn't have more fun on a different more "advanced" kite, but really no need to worry about that now.
4) Should I buy a full set as a package?
All depends on the price.
Be aware of compatibility between brands if you decide to buy things piece by piece. Will get a lot more expensive if you end up with 3 kites and 3 bars. I use the same bar for all my kites.
5) I have read a lot about Core, but they are fairly expensive, should I go with a little more affordable brand to start?
I got nothing against Core, but I really don't see why anyone new to the sport would pay the premium for those kites. It is not like kiting with Core is much different, if different at all, than other kites. It is not like I'm dreaming up "upgrading" my kites to Core sometime in the future (I have tried Core once and I didn't even like the kite
- doesn't mean they are bad of course).
Buy a Core if you want one, not because you think they are better. Some of them look quite nice I got to admit. Quite stylish design compared to many brands that got "messy" kites in my opinion.
6) Should I invest more in my first board or the kite (would I replace the kite a lot faster than the board as I increase my skills)?
In my opinion you will outgrow a board faster than a kite, but this is also exaggerated on this board in my opinion. My guess is that there is quite a few very advanced riders here who got different requirements than most kiters do. I have loaned my old "beginner friendly" board to very good kiters and no-one have ever said it wasn't "good enough" (and I don't think it had anything to do with not hurting my feelings). Still - I think you might replace your board before kites. Especially if you start to do some serious jumping.
7) I was riding a 12m kite in good wind and a 14 in lighter wind, but my weight has decrease from about 210 lbs to 185 lbs since my last session. What size kite(s) should I get? Board size(s)?
Already answered I guess. As for the difference in size between kites I would recommend a multiplicator somewhere around 1.35-1.4 as a rule of thumb. 17 / 12 = 1.142 and that is borderline in terms of 17 being too big and 12 being too small in certain conditions. I would never have bought a 12 and a 14 as they cover too much of the same wind range. It will slightly depend on what kind of kite of course, but as a rule of thumb I think it works well.
8 ) Any recommendations to help save money?
Call. I have gotten fairly good deals by just calling shops. Especially if you are looking for a lot of equipment. A shop might have an "old" kite etc. they can throw in and so on. Calling works a lot better than sending emails in my opinion.
9) Any gotchas to avoid?
10) Travel bag advise?
All the same to me. I bought an used one. How do you wear out a bag? So paid like 1/3 of the price. A small tear in the side, but that has never caused me any issues. And that bag has been around the world quite a few times now.
11) Can I get parts or repairs to my gear if I am traveling?
12) One instructor told me that more established brands will be easier to get parts for around the world. Thoughts?
Parts is really not a big deal generally. If you canopy rips or something it doesn't matter which brand the kite is - it can usually be fixed locally by someone. If a line snaps the same - even if line length might be an issue some places. And also not sure if you end up with a Y-style bar if that is potentially more difficult to fix than V. Personally I would recommend going for a brand with a V-style bar, but others might disagree.
I have never ever needed to do any repairs on my equipment (got one bar with some issues, but it is my back-up bar so).
13) Thoughts on buying used gear. Ebay? RealWaterSports?
I have bought 5 kites, 2 boards, 1 harness and 1 bar used. Saved more than 50% doing so. Never had a single issue with any of the equipment. A lot of kite equipment is never used much. A lot of people start kiting, but give up quite quickly. And a lot of team riders etc. get kites that they never use much. Two of the kites were basically as new. If the guy had told me they had never been used I would have believed him.
Also kites do last for quite awhile. My first kite I bought used several years ago. I used it. Then I sold it to a friend. He used it. And now he sold it again and it is still flying without any issues.
Obviously buying used comes with some risks. I always try to find out who the person selling it is etc. Doesn't mean I will never end up buying something I shouldn't have had, but I have never ended up feeling cheated (that goes for motorcycles etc. as well).