Desktop Application

hey.
i will write the description of the program i want and you tell me the cost and the time :)

1: a program that the user will run

2: the user inputs a username and presses start,

3: the program sends that username to my gameserver

4:the gameserver generates a random string ( SDFsfdSaw2fF) and sends it to the program( i will do this serverside )

5: the program saves that string ( it will need it later )

6: the program will launch an exe that is in a folder

7: when the program runs the exe, it needs to check the task manager of the user, find ALL 3 letter .exe running ( asd.exe ) and only 3 letter exe tasks.
check their path and scan all folders and subfolders in that path for file names and folder names ( i will make a list of file names ) ( example AdrenalineBot.png or updatersettings.ini or updater( folder ) )
v2: if it finds such a file in a folder in the path of the 3letter exe that is running, it sends a message to my gameserver

8: every 60 seconds the gameserver sends a request to the program asking for the random string it sent in the begining.

9: the program sends that random string back to the server

UI information
i want a small box with a field for the username and a start button, minimize option ( minimize to tray too if possible ) and an x to close the program

i want to be able to set the background of the program and the image for the start button( not the user, only i will be able to change them )