SHIPSFollow

the only ship you can upgrade to, as a rebel, is the Y wing, check your level certifications to make sure you can fly it though. to get the best prices possible do a vendor search. if you have bypassed the y wing already, and can use the longprobe, then go for that one, as 2 guns are better than 1. the y wings have a pretty good mass capacity, so you should be able to fit whatever level weapons/equipment you can use quite easily. the best equipment tends to be player created, rather than looted. my own advice would be to fit an engine with a good pyr, speed is good, but if you can't turn well, you'll be an easy target.

There is a crafted version of your starter ship that usually has way more mass than the starter its a tier 1 ship but it can hold missles and chaff, if they fit. Actually the tier 1 crafted ship can be modified to kill tier 3s. Qhat you want to buy first is a good shield and those can be easily crafted. This will relieve you alot. For the beginning you can get by on looted parts, but you really need to invest in a new chasis the starter is just ***. I doubt the tier ship will cost you anymore than 10k or 20k.

also you get no booster on the starter ship which is an after burner

at a vendor in a static city theres tabs up top to click to do galactic wide searches. you right click on the list to create a waypoint to the vendor that item is being sold at. if you learn to do galactic search you can actually make creds off ppl who dont know how by knowing where to find what they want and some charging extra when you trade to them

yeah, it seems to work both ways, and for freelance also.
As for your second question, If the Tie fighter is the best ship you're aree certified to fly then I would say you just need better components.

Missles will go on the y-wing and most of the other ships out there. The key thing is mass. Some of the faster ships lack enough mass to hold good parts unless you are fortunate enough to know a Shipwright who can reverse engineer some parts for you.

You also need a good capacitor. Having strong guns on a ship won't do you much good if your capacitor is weak. You will see what I mean if you start shooting up the place and then your guns won't work for a few seconds until the capacitor recharges some.

Don't focus too much on a good booster. The higher level you go, the more mass generally. Unless your ship has a lot of extra mass, getting a good level 2 or 3 booster is fine and will allow you to fit other parts on the ship that are more vital.

The Y-Wing has space for two main weapons (i.e. lazer cannons, ion cannons) one of which is the turret that can be operated by another player, and one spot for a ship ordinance (i.e. missles). You have to load a missle launcher in the ordinance section and then ammunition for the ordinance in the ordinance section. Try teaming up with a structural trader or join a guild. They can usually help you with components and gaining XP.

P.S. I am a trader myself and as long as you provide me with the raw materials I don't mind crafting things for nothing or next to nothing. Most traders who are looking for xp feel the same way. Most of the work put in by traders is hunting for the various materials.