5D3 sales for ~$2500 have happened already and are bound to happen again. Just get one then.
pardon my stupid question, but is there a way for me to know when such sales are going on?
I don't monitor this forum daily - should I ? would it be posted here? Or perhaps there is an easier way?
1) keep an eye here as I see CR post from time to time when massive rebates occur.
2) keep an eye on adorama ebay store and other legitimate vendors with ebay presence.
3) keep an eye on canonpricewatch.com especially their deals section
A few fly-in-the-ointment comments. Timing wise, we just had the rebate cycle at the end of the year and you may have missed a good chance, but these chances reoccur periodically. You may just have to wait some. Also, these fire-sales happen and end so quickly, you need to have a firm price point and game-plan and clinch the right deal when you see it. Few 100 units sold and you could be out of luck if you are thinking about it. If you are in Europe or certain countries, all bets are off as I hear customs penalizes imports with added tariffs at entry. This is to ensure you buy locally and support native vendors and pay higher taxes.
Regardless, always choose reputable dealers as this is a purchase over 2K. In your desperation to land a good deal, never compromise on that. If t looks too good to be true, it probably is. Good luck.