do you have your tactical display (the radar thing) on screen, if not bring it up with shift+T. To have a successful mission you have to follow the waypoints wich you find by following the blue line on the tactical display.
For CAP missions one of the waypoints is a "loiter waypoint" (see your briefing), at that waypoint you have to fly around for about 5 minutes or so and then fly over it again before you wil get a bleu line to the next waypoint and can proceed with the mission.
For the interception you or your wingmen will have to destroy at least one of the indicated targets you wil run into, on the tactical display you wil see a purple arrow which will lead you to them, once they are in sight you can identify them by their purple color on the tactical display or purple labels.
Don't know about recognition missions, I don't fly them often because they have not a great impact on the campaign, and I can't get them successful either.
Once you have done all that you will get a screen close/go to briefing room once you return above your home base, after that you can close-land-escape-end mission or just go to the briefing room to end the mission successful
The price of a plane is defined by the dates for it in the techtree of the campaign xml file (stock campaign called fortresseurope.xml in your CFS3/campaign folder) and the entered/left service dates in the aircraft.xdp file from the plane. If you want to change the campaign file you can do that easily in notepad (but backup first). If you want to know how just do a search for "changing campaigns" on this forum or the forum at
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