What is the best way of improving the power of my inline 4?

So my vehicle is a 2011 ford escape xlt with awd and an l4. I would like more power from it. Getting the v6 was not an option. And I will not be getting a different vehicle. I will be using this vehicle for a long while and would like to just give the 4 cylinder a little extra. What is the best way I can go about this? Stock it should have about 171hp. I'd like to try and get it past 200. I do have some money but I can't be putting anything like 4 or 5000 in it. I don't know as much about cars as I would like so anything you can tell me is helpful. Unless you are telling me not to bother then don't waste your breathe. If you know of any parts and you can link it to me for my model it would be much appreciated.

Unfortunately, it costs a decent amount of money to get any noticeable gains out of a car. If you couldn't afford the V6 option you wanted, you can't afford the performance enhancers that it would take to get an I4 to match the V6.

Cheap mods, including ram/cold air intakes don't increase your power much without other mods to accompany it.

How much money are you looking to spend? How much aftermarket support do you have for your engine? Does said engine respond well to mods? Gaining 30 hp on a 4 cylinder engine is not easy. You'll at least need an aggressive aftermarket cam, headers, and exhaust to achieve those numbers. That will set you back a good $2000 if you are doing the work yourself and if those parts are readily available on the aftermarket. If you want to boost the engine, the internals will need to beefed up on top of the cost of a good turbo which is potentially way more expensive to the point you may as well attempt swapping in the Mazdaspeed3 3 engine (Ford and Mazda vehicles share lots of parts.)

You might think I'm wasting my breath, but here's the reality - you aren't going to add 30 HP to that car without spending a significant amount of money and/or compromising the reliability and long term durability of the engine and possibly transmission. You can probably get a CAI, catback exhaust, and a reprogram for 2K or so, but combined they won't give you 20 HP let alone 30. You can't get a 20% increase without serious mods.

So - my advice - do nothing for now, take that money that you might have spent searching for a few HP and sock it away, and then the next time you are ready to buy a car, buy one that meets your performance needs from the start, pay the extra for the V6 or turbo or whatever.

Do engine mods after brakes suspension and transmission.

It is as good as it will get. The small low torque motor has its limitations, so learn to live with it.