We fly out of Buffalo exclusively now. We live in Burlington - about 45 minutes west of Toronto. We can leave our house, be through the border crossing and in line to check our bags at Buffalo Airport in 90 minutes. We always leave earlier than that just in case, but we cross at the Peace Bridge and have never waited longer than a couple minutes (keep in mind we always cross early - anytime between 3am and 8am is our norm). As far as toll roads go, I can't remember exactly, but I think the only toll you encounter is for crossing the bridge and I'm sorry, I can't remember how much that is. We usually park at the airport in the long term lot (there is always a coupon on the airport website). I think it costs us somewhere around $50 for a week. Buffalo is a fantastic airport to fly from ! It is so much cheaper to fly from the US (on our trip last month by flying from Buffalo we saved about $1200 as opposed to flying from Toronto.) It's not huge so very easy to get around.
If you couldn't already tell, I'm a big fan of Buffalo airport and we'll continue to fly out of there every chance we get !