Look for another contractor. They likely don't do the work they are supposed to and don't honor their warranty. Here are all the issues I have with the work they did:
Interlock:
1) they were supposed to raise the grade by 5-6 inches to avoid the need for a half step that was there before. They didn't raise the grade even 1 inch and instead went ahead and installed an extra step and didn't even say anything to me about it. I saw it after they had left
2) in the quote I had specifically asked that they put down 1 foot of base gravel in line with unilock technical guide and they even charged me extra for it. When I dug a couple of post holes after they finished putting in the base, I noticed there was only about 6 inches if not less.
3) before putting down the base material, the same unilock tech guide says that a permeable weed barrier fabric should be put in which helps prevent spread of the base material. They did not do this
4) when they finished, they left quickly and didn't finish putting in the polymeric sand on all the sides and had no intention of coming back to do it until I called them.
5) I have 2 semicircular window wells where the interlock was being installed. When the owner, Giorgio, came to quote me, he forgot to note the window wells so after a follow up call, he drew them as rectangular. When the guys showed up on site, they were confused by this even though I explained to them multiple times that they were never supposed to be rectangular. After a lot of back and forth I agreed to do a modified rectangular design which they then completely ignored and did the same thing they mentioned at the start. It looks ugly.
Asphalt:
This was the one thing I was happy with because initially it looked great. I even kept the car off the new driveway for a month (way longer than they suggested was needed) to ensure it cured sufficiently to avoid any tire marks. After parking on it for about 1 month, there was already a small crack in the middle of the driveway. They guy they sent out to take a look decided within 2 seconds that it was caused by tree roots and therefore not covered by the warranty. A quick Google search shows that tree roots are not the cause of driveway cracking if the tree is more than 5 feet away. The closest tree with any significant roots is 20 feet away. It also didn't seem to matter to him that the neighbors driveway (done by them at the same time) also had a crack about 30 feet away from the one on mine. There were other things that made no sense for it to be caused by roots but he would not budge and his solution to fixing it was to put some polymeric sand in it. I am no expert but I have never seen any cracks on city roads or other people's driveways with polymeric sand in it...but it sure is a cheap way to get out of doing a proper fix.
In terms of customer service, the office staff and the excavation/asphalt crew were very courteous but the interlock crew barely spoke any English and was very difficult to interact with.
Based on my experience, they'll do a job for a competitive cost but they won't do it right.