Glass can be drilled, it's about $30 per hole for most places, and they don't guarentee they won't break it. If you're going that route, buy one that's already drilled. If your garage is heated, I would put a sump down there and run it from the garage (as long as it is clean as well, and you can separate the area from where your car will be, exhaust will mix with the water and go up to your tank otherwise). As far as tank size, every time I buy a bigger tank, it's big for about 3 months, and then it's too small again. Buy the biggest you can afford and fit (make sure it can be brought up to your 2nd story condo through available stairs, as well, or you might end up having to rent a crane and take out a window like a friend of mine did for his custom tank and stand), you'll outgrow it slower than a smaller size. As far as the move, I would get the new tank ready as far as some substrate and water a couple of days in advance, then move a few things at a time if you can, otherwise everything at once, just dump it into the new tank, the only thing you're really changing is your water (unless you have a DSB, in which case I have heard you need to be careful about stirring it up, it can cause toxicity in your water and kill everything) since your bioload is the same, just in a bigger space. Every time I move my 125 I move it all at once and refill it with probably 95% brand new water and then acclimate and dump the critters in. I've done this several times, and the only time I had disaster was when I got sick and went to the hospital and no one could release my fish for 3 days (actually only lost a couple of fish out of many, I put a few in a 5 gallon bucket which was lined with a 13 gallon kitchen garbage bag that was filled with around 4+ gallons of water and then tied it off with air in the top) and when I transferred a baby lion and baby trigger tank with crushed shells as the substrate - the tank cycled when filled again as the shells didn't hold bacteria well due to their non-porous nature. Good luck with the move, I would definitely suggest at a minimum getting your water ready beforehand (I use 32 gallon rubbermaid trash cans to mix and store water).
