Woah this one idk where to start from.. got so many options with your budget
Not gona recommend samsung cause of their ****ty toner cost and poor reliability. No offence if you are a samsung fan as it is base on my and other customers options

Canon MF4720w $199
Print, Copy Scan (wifi) (No auto duplex printing)
Toner
$105 2.1k page yield
1 year on-site/carry-ing (not sure but cfm is 1 year) warranty
No document feeder so you may have problems doing multipage to 1 pdf file scan
Fuji Xerox M205fw $349 +$100 ntuc vouchers
Print,Copy, Scan, Fax(ignore if you dont use fax) (wifi) (No auto duplex printing)
Got ADF so can do multipage to 1 pdf file and auto scanning with ADF
Toner
$55 1k page yield
$95 2.2k page yield
2+2 years on-site warranty
Brother MFC-7860dw $348 + x mini speaker? lol (Got apps to print from iphone and android)
Print, Copy, Scan, Fax(ignore as well) (wifi) (AUTO DUPLEX PRINTING)
Got ADF so can do multipage to 1 pdf file and auto scanning with ADF
Toner
$54 1.2k page yield
$92 2.6k page yield
Drum(only brother special need to change this)
$98 12k page yield
3 years on-site + 2 years carry-in
Fuji Xerox M255z $399 + $100 ntuc vouchers (basically functions are similar to brother MFC-7860dw except this machine do not have apps to print from mobile phone and have nicer print out quality)
Toner
$105 2.5k page yield
$180 if buy 2 together in one packaging
2+2 years on-site warranty