Just file forms I-130 and form I-485 together with the Chicago Lockbox.  It should be done in less than 4 months. No need of anyone's advise. Just use USCIS website.  If you are USC, the process is simple and easy.  Once you leave the country, the process will take much longer since your I-130 after approval, will be routed to NVC and then to the consulate.  It would be stupid to apply from abroad. NVC's officers are laziest on earth; worse than Nepal.