before buying a lawnmower brill ms 254 b exact all your options, equipment, appearance and warranty from the seller. please note that we are not engaged in the sale and manufacture warranty.

How would the previous sentence be correctly capitalized?
Answer: Before buying a lawnmower BRILL MS 254 B exact all your options, equipment, appearance and warranty from the seller. Please note that we are not engaged in the sale and manufacture warranty.
get people to take a photo in the store and post it- you'll need to ensure they tag you in it, or mention your store.

How would the previous sentence be correctly capitalized?
Answer: Get People to Take a Photo in the Store and Post it- You'll need to ensure they tag you in it, or mention your store.
synack, a security-testing-focused company that uses "highly vetted ethical hackers" to crowd source solutions

How would the previous sentence be correctly capitalized?
Answer: Synack, a security-testing-focused company that uses "highly vetted ethical hackers" to crowd source solutions
program modification: sometimes, not only virus worm:win32/bagle.gx@mm or malware max secure registry cleaner but also common softwares possessing the ability to modify the inner functions of cnb_0324.dll, which means other programs can't find this dll file again.

How would the previous sentence be correctly capitalized?
Answer: Program Modification: Sometimes, not only virus Worm:Win32/Bagle.GX@mm or malware Max Secure Registry Cleaner but also common softwares possessing the ability to modify the inner functions of CNB_0324.DLL, which means other programs can't find this DLL file again.