I always recommend glass over bodies, but in this case I can't. Upgrade to the 5D Mk III first, then start saving again and get the 200 f/2L. Get that lens, because I can tell you, as good as the 135L is, the 200L is even better. Whether you make money off these purchases or not, I think your photography means enough to you, that I can guarantee you that it will be worth it to you. 5D Mark III about $3500, 200 f/2L about $5999, total purchase value $9500. That's not that big of a deal if you spread it out and your photography will go where it hasn't yet. The 200L loses very little resale value anyways, for financial security.