If you and your wife like the stand/canopy, get it!  The absolute worse outcome is overpaying a bit for the combo and that's not the end of the world.  I was a carpenter in a past life and currently own or have easy access to all the tools required to do it well and I wouldn't build my own.  It's a tremendous amount of time and the costs savings is negligible assuming you're counting your time and "paying" yourself a decent rate.  Another nice thing about buying a well built combo is that you can use them both for a long, long time.  I've had the same stand for 3 different tanks and it still looks good enough to sell if I ever want to change the foot print.  There will be plenty of opportunity to save money by doing something yourself.