Notes

DISCLAIMER: This is going to be a little bit long so if you don't feel like reading it there will be a TL; DR at the bottom of the post.
Hi to everyone, I am 18 and a university student. This is my first post here so I'm sorry if I bore you too much or irritate you with my broken English. So basically, my hair is like in between on everything. It is actually wavy but I mostly keep it short and try to manage it with a blow-dryer and a brush so it looks pretty much straight if you look at my face directly and people who are shorter than me thinks my hair is completely straight as they can't see the top of my head, which looks bad in my opinion with all those uneven waves. For clarification I don't use any gel, wax, mousse etc. I only use "Pantene Elixir with Argan Oil" (combined with a hair conditioner from a brand called "HASK") as a pre-styler and I find it quite useful as it makes my hair much smoother than it actually is and I live in Turkey, so I don't know if they sell these products somewhere else. When it comes to colour, I classify myself as a blond but not as blond as a typical East European and it certainly is not black, it is kind of something between blond and brownish. (my hair is quite blond in Turkey standards where almost everyone has black hair.) And in the photos below the first 3 are how I usually keep my hair and the last one is a photo I took today after styling my hair (longer than usual and I will probably get it cut it next week.) My questions are that should I get a “Keratin treatment” (I seriously have no clue whether my barber is capable of doing it well without damaging my hair and consider I live in Turkey and I don’t pay much for haircuts as my barber is not a high-end barber.) to get my hair utterly straight? If you recommend getting a Keratin Treatment how should I style my hair and should I change my hairstyle? Lastly, I shampoo and condition my hair every other day and don’t want it to look too greasy and shiny is there any product type or brand (putty, clay, paste, gel…) you would recommend me to use? (I am on a budget as I am a university student)
TL; DR: My hair is in between on everything (half straight half wavy, kind of blond kind of brownish) should I get a Keratin treatment and change my hair style and a product advice (putty, paste, clay, gel…) which won’t make my hair look shiny and greasy after a day? (I am on a budget.)