Making the jump into Festool and having a nice budget like that is awesome.
As Bob mentioned, plan your purchase to take advantage of the combos:
TS55 + MFT3 combo. The MFT comes with a 1040 rail (42"), plus the TS comes with a 1400 (55") rail standard. So, from the get-go you've got those two rails as your standard start.
You can usually arrange to substitute (for cost diff.) guide rails if a larger/smaller size seems like a better long term choice. Remember, you can always use a longer rail to make a shorter cut... but not the other way around. So, as a suggestion, get the 75" with the TS, and using that with the 42", you can rip sheet goods, and cross-cut easily and conveniently.
CT26 + (take your pick here-- I'd suggest a sander like either Rotex) combo
You can usually arrange to substitute (for cost diff.) CT hoses and/or longer length hoses. The 27mm hose works with every Festool (minus Kapex only?), but the 36mm hose has better pickup. The 36mm IMO is ideal for the TS55 and the routers.
For $50 or so, Bob can supply you with a 36mm to 27mm adapter "tail", that then allows you to use every tool. Well worth it, IMO.
I would personally advocate away from the Boom Arm, if you have a fixed-area shop. The Boom Arm is fantastic if you're going to be moving the CT around a lot and want that overhead support in a bunch of different places. But, if you'll be primarily in a stationary spot, you can build a boom-arm-like support for about $15 and in 30 minutes.
You should plan a decent amount for accessories.
Suggested first choices: Clamping elements for the MFT, MFT "F-clamps", extra CT bags, probably a CT brush or crevice tool. Just plan on about $200 for MFT and CT acessories.
So, with the above tools you can make simplistic projects. Bookcases, squared tables, simple picture frames and boxes. Heck you can even make cabinets and finish them.
Additional thoughts:
Domino: The ultimate in a joinery tool. You need the Domino tenons, and figure you'll wind up with at least one additional size of cutter. Within a few months, you'll want more... so just plan that this kit will cost you $1000 total. Now, there are a lot of ways to do joinery, many of which can be VERY inexpensive (e.g. handsaw cut M&T). I *love* the Domino, and actually it was my first Festool. But looking backward, and since you're looking to jump in, I wouldn't consider it a first-round purchase. Second round, for sure. [embarassed]
Routers: Routers are the most versatile power tool, and the Festool routers have no peer. There are a ton of other threads to help inform your decision of the OF1400 vs. the OF1010. Definitely get one. They're awesome. Heck, get one of each and the MFK, too. Seriously. [wink]
Sanders: There is a veritable armory of Festool sanders. The widest and most plentiful area of Festool tools, it seems. The Rotex kick butt, plain and simple. They're a multi-use powerhouse that also has a finer touch when you need it.
For the time being, don't get overly caught up with all the specialized sanders (LS, DTS, DX, etc). Later, when your projects have better defined your needs, you'll almost certainly pickup one or more of these. But you can get away for a long time without, or using another method for those pesky corners.
With either of the above two tools, you're looking at a fairly sizable investment on accessories. For sanders its a matter of sandpaper assortment. Figure on about $75 to build a decent starter variety.
For the routers... yow.. You can pop $150 just on physical accessories (edge guide; rail adapter), and another $100-$150 easily on an entry-level variety of router bits and what-not. Let's assume you already have a bunch? 1/2" or 1/4" shank? If the former, the OF1400 is the way to go, to make use of your existing router bit inventory.
Miscellaneous:
Drills: They rock, but ... they're drills. You can drill and drive screws with many, many choices. And you probably already have, like, 5 drills. Right?
Save your bucks for Festool's prime players until you've run out of green & blue goodies, then complete the collection. [big grin]
Kapex: I don't have one, so I'm not really qualified to compare it to anything. I really admire its marketed features, but just can't swallow that it's nearly triple the price of my current SCMS (Bosch 4410). It's a budget buster for sure, and keep in mind you can get a Festool router AND Jigsaw, AND Rotex for the same overall price. With the TS55 and MFT you can do all the same straightforward cuts that a miter saw does.
Organization stuff: Okay, you might not be ready for this, but if you get bit by the Systainer bug, there's a lot of spending that can occur. Assuming you get a sander, you are best served organizing your sandpapers (e.g. Sys abrasive box). If you get the router, you'll soon be needing the router bit Systainer to hold bits and various accessories. A Sortainer is invaluable sitting atop your CT, always at the ready with clamps, bags, nozzles, pencils, rulers, etc, etc.
Good luck, and happy Festool'ing! Please make sure you post follow-ups whenever you decide on your choices. There are NO wrong answers on the green slide.
