3 nights, £86 per night for the room, not per person. £625 all in with flights basically, so £300-odd each. Not bad.
Just trying to find hotels on street view. East Berlin certainly is a bit soviet stylee

So much roadworks going on around there although I guess that's all done now because according to streetview the Andel was still under construction...
I think you could do better than that, since I paid £455 for flights & 5 nights at the andels with breakfast included.
I also disagree about the breakfast at the hotel issue, sure I wouldn't pay anything like £15-£20 pp as I have seen it being charged, but the andels worked out at £67 per night inc buffet style breakfast. Since eating out for 3 meals a day for 2 is usually the expensive part of a holiday, just fill up on the buffet breakfast and you only need a snack for lunchtime, then it's just the main meal.
To be fair though, Berlin was fairly cheap for food, especially the 'snack' food of which was a good quality and everywhere. It will be more expensive around the alexanderplatz area, as that is touristy - eg. 3 euro for a currywurst there or 1.30 further out.
Some places we ate at that I can heartily recommend (more where the locals eat and had been recommended by german friends)
http://www.thebirdinberlin.com/ The Bird at Am Falkplatz 5 - excellent burger place with attitude. Honestly the best burger meal I have ever had. Definitely book though - took us 3 attempts to get in!
Just round the corner, since we initially couldnt get in there is (and was recommended by the bar girl at the Bird)
http://www.tebla.com/restaurants/berlin/asteria Asteria on Schonhauser Alle. Greek restaurant - oh my...masses of food, portion sizes are massive, most of it complimentary (No joke!) and continuous free ouzo!

I left there on my hands and knees completely stuffed and as drunk as a skunk (10 - 12 shots of Ouzo + a big glass - all free) it cost ~£34 euro for 2. Salad starters, 2 x fruit platter deserts and coffee and biscuits all just given to us for free without asking.
http://www.tiergartenquelle.de/index.php/de/ Tiergarten Quelle on Bachstrasse. Spit and sawdust local tavern - good price, big portions, typical german food. Not as good as the above 2 but better than any expensive 'chain' restaurant in the centre.