Question on WRX bike & ski racks (roof vs trunk vs hitch mount) X-post from r/mtb

Fellow adventurers, I need help deciding on a bike/ski rack! I've been doing a lot of research on the internet over the past few days. I drive a 2013 WRX 4 dr. sedan (Brand new, got it last week!). I ride a Trek 4500 hardtail but may upgrade to an all mountain FS in the near future. I have a few options, but need to know the best for the money. I am an avid biker in the warmer months, avid snowboarder in the winter months. Basically I'm trying to condense my purchases and just try to get a fit all solution, although I'm not sure that's possible.

Obviously most ski racks are roof mounted, which makes sense. However, I do not think I would like to mount bikes (I may also need to drive cross country) to the roof because I hear they are noisy up there and kill your gas mileage.

Then we have trunk and hitch mounted options, which I feel are better. But a hitch would leave me having to get one installed by a mechanic, which adds even more time and cost (my car doesn't have a hitch installed). Are trunk mounted options reliable? Also, is there any combination ski/bike rack trunk mounted options? I can't seem to find anything like this, not sure if it exists. Figured I'd ask here.

Will I have to buy a roof rack with ski/snowboard holder for the winter, and use a trunk mounted bike carrier for the summer? What is the main solution to this that everyone does? I'm sure I'm not the first to come across this. Also, I was looking at the Saris Bones, can anyone recommend that or another model/brand?

Any comments/recs from WRX owners are appreciated, thanks for the help!