Welcome. You you can save a lot of money doing stuff yourself and you can do most anything with a bit of research and asking a few questions. When I got my MPS I had no idea what I was doing either, but now have a fair few mods, with almost everything done myself.
For power, I'd suggest starting with a 3" intake, rear engine mount, turbo back exhaust (or just a second cat delete for 90% of the gains), hpfp internals (don't skip this one!), maybe a tmic, and a good tune. That will get you very good gains on the stock turbo.
Tunehouse have a good rep but I think their packages are very expensive compared to diy. Wolf racing seem to be ok for parts and iv had no problems with them so far. Yeah, stay away from MPS Garage. They are dishonest, give no ****s about their customers, and are banned from this site. Otherwise, ordering parts from the US (edge autosport and direct from companies like corksport) is the best option, even with the shitty dollar
Try 2xs racing for exhaust stuff (also intakes and some other stuff). He does awesome work with ceramic coated mild steel exhausts and knows the MPS very well.
Good luck
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