I can drop a few things to check.
IAC valve dirty. Free and easy to clean. I use electronics cleaner and cotton swabs ("Q-Tip") to clean and follow with a drop or two of light oil where the shaft enters the solenoid. I clean it at about 30,000 mile intervals (when I change the fuel filter) or "as needed" which happened last year (hard to start and would not idle).
Replace Fuel filter. About $20.00 and easy (with the fuel line connector tool).
IAC valve faulty. About 20.00 to $80.00 depending on whether aftermarket or OEM, but easy. Mine is original with 275,000 miles.
Fuel pressure and volume. Free to check.
Electrical relating to fuel delivery.
Vacuum leak.
Fuel pressure regulator. I haven't heard much of these failing, but maybe.
Fuel pump. Prices vary greatly. Kind of a pain to replace.
MAF sensor dirty or faulty. Inexpensive cleaner 30.00 to $60.00 to replace and easy.
That's it for now.