Garbage: we ended up using Expert Waste Services for bins and has worked out really well. They charge a flat rate for delivery, then $75/ton. It works out to roughly $450/bin for a 40 yd. I did have one that was $625 (the very first one), but all the rest have been in the $350-500 range. We have used 5 x 40yd bins thus far, and 3 x 14yd concrete bins.
Windows: If you want to cut down on the costs of windows and are comfortable installing them yourself - ask for a supply only contract. This is what we did as the window company typically adds ~80% for install. Thus, if you have an $18k window order, 10k is for the actual window, and 8k is for the install.
Truck: I bought a truck for this reno - it was a decision well worth it. I will sell it when the reno is done for roughly what I paid (give or take $1000).
Lowes: I signed up for a business account at Lowes. You save 5% everyday, but they also have events (roughly once a month) where it is 10 or even 15% off. It adds up quickly! I also find HD is quite a bit more expensive on just about everything.
Bobcats: Don't be afraid to rent the bigger equipment at HD. The bobcat was very useful when pulling out the old wheelchair ramp. It was able to lift 3ft sections of concrete at a time into the concrete bin.
Rentals: Think about what tools you would need to rent a lot. I ended up buying a concrete saw on Kijiji and will probably sell it for roughly what I bought it for. I use it roughly once a week vs. the $100 rental charge each time. I also bought a conga hammer...well worth the investment.