You've already received professional and enthusiast tips from other experienced people on this thread...
Allow me to give you my amatuer, non-pro take...
I have my projector temporarily installed in a room with black ceiling, dark wood floors and cream walls... A standard, price-of-a-nice-dinner-for-two-with-cocktails, grey non-ALR elite screen with black borders was transformative... No comparison vs. the wall on it's own... But more importantly, it's better than our newest local cinema... How?
Did I magically get a unicorn Epson? Does physics work differently in my house? No... The local cinema has very bright exit signs... Bright enough to raise the black levels of their screen to a light grey...
My point is this, if you want to enjoy a quality image, that does justice to your expensive projector and to yourself, get a proper screen and above all
avoid the basic mistakes...
You don't need to turn your living room into a cave, or to settle for projecting on a wall. Just buy an expensive high quality retractable screen, or install a cost effective, but good fixed screen that fits your decor or can be concealed/integrated (lots of interior design ways to make these look good)... but most importantly, avoid the basic mistakes.
Personally, even though the screen I bought is basic, and will be replaced with an accoustically transparent screen when the dedicated room is done, it has made a huge difference in my film watching... I think you will find that to be the case when you get your screen.
Enjoy your movies