You need to do some research yourself in this forum as well in
projectorcentral.com (for reviews and all calculations to set it up). Just in case you are not getting 4K projector now, following FHD projectors are south of 1 lakh and easily available
Epson TW5300,
BenQ W1050 (seen it in action and loved it. Also available in Amazon.in),
Benq W1210 ST (ultra short throw projector, available in Amazon.in)
Optoma HD27 or HD143x
and well reviewed
XGIMI H1 if you are looking for Android projector.
There are many and may be if you look around you would get your original choice Epson TW6700 near about 1 lakh.
Another way is get it from Amazon.com/Amazon.de. I use Epson TW5210 (link in my signature) bought from Amazon.de. In similar line you have to do some research and get anything from Epson or Benq or Optoma.
For screen, I would be wrong to say much about it; because I, myself, project on wall. But one thing for sure, NO pull down or low cost motorized projector screen. For motorized get something well known brand and/or search in this forum and get ideas about screen and make/buy a fixed one.
Darkening the room is always good, but not necessarily to be black only.