I'll admit not being all that familiar with hardscaping in northern climes, beyond being aware of its difference due to frost heave, but the driveway and walkway pavers sound like DIY projects to me.

I've successfully used asphalt patch products to fix cracks and holes by hand. I'm not talking about tar patches, but, essentially, bags of asphalt concrete that you can stuff into the cracks and holes and compact to make them effectively, over time, part of the existing blacktop.

As far as the walkway goes, you should be able to fix that by digging dirt from underneath the pavers and replacing it with some stone and stone dust.

In both cases, you'd want to compact it, and doing both at the same time would be a great time to rent a plate compactor. It'll be a hell of a lot easier than tamping by hand.