Bookshelf speakers are more suitable for a small room right? And it requires a proper stand as well making it kinda difficult to find a proper setup for the set. I’m all open now to suggestions whether it’s a bookshelf-typed or floor-standers, main concern would be which brands to go for, for a best possible best bang for my money planned on spending with these setup without sacrificing sound quality.
Ceiling is flat with one ceiling fan of course. Mounting wouldn’t be much of a problem as most probably looking for a wall-mounted ones if I’d go for the direct firing overhead speakers, concerns would be wire management in which could be resolved by concealing it under those acoustic wall foams (cheap China-made one) but the cost of these cables in general. May I know what kind of cables are you using for your setup there in your siggy and which type of connections? Brands wise now looking for Klipsch (as per your recommendation to other forummer, QAccoustics, SVS to name a few).
And I would most probably go for the Denon AVR X6400H, for future upgradability, and full support for a 7.1.4 without external amplifier. Never really bothered about a proper HT setup before but since now in a planning stage, well F me, the price of the top-fledged AVR like X6400H is like building a mid-ranged desktop pc!!
Recommendations for reputable shops and good price will always be welcomed as well.
Anyway, Still doing some readings of my planned setup as I don’t like everything to be handled by the shop. I wouldn’t mind paying but definitely would mind if got cheated. Lol

Bookshelfs usually cut out at 50Hz floor standers at 35Hz and can be placed on a long TV rack to save on stands. If you plan to get a sub then anything below 80Hz goes to sub.
Well if your budget is 12k. Good sub min 4k gone. so not much for your other speakers and amp. Unless your budget can expand. Either look for 2nd hand amp/sub then start with 5.1 slowly upgrade to what you want. If you are having a dedicated HT room then 7 speakers on the floor is doable or else 5 would be max what you need cause speakers cannot be placed too close to wall unless you get wall mounted speakers or add damping behind speakers.