Download, install and open this program
(This program is easy to use and it works on Windows 7 and Windows Vista)
After you opened the program point it to GTA San Andreas folder(C:\Program Files\Rockstar Games\GTA San Andreas)
Now...go to "Scene" tab and choose what part of the game you want to see and then press "Render"
After the map will appear navigate where you want with this how keys: slow "W,A,S,D"
Now go to "IPL" tab and select the same as you selected at the "Scene" tab.
Now to place a object press right click anywhere on the screent and press "new"
After selecting press "OK"
In the left of the program you have:
Now you can do everything...the limit is just your imagination!
Tip: if you want a obhect and don't know how/where to find it just double click on any object and then right click and copy and then select the place where you want to place it!