「目{め}の不自由{ふじゆう}な方{かた}のものです。モノをおかないで!」
おかないで = 置かないで = "please don't place"
This is a sign occasionally seen near the Braille blocks for the blind in public places -- in particular, on the sidewalks.
「目の不自由な方」 means "the blind".
"This (= The Braille) is for the blind. Please do not put (and leave) things here (on the Braille blocks)!"
Not sure where you get "blind spot" from. 「方」 means "persons" here.
「もの」 in the first sentence describes "intangible possession". The Braille blocks "exist" for the blind. A sensible orthography choice indeed.
「モノ」 in the second refers to the tangible items such as luggage, boxes, etc. that people might possibly leave on the Braille blocks. They could have used the kanji 「物」 for this one but went with the lighter-looking katakana.