Chimney Advice

[Tug0628]

Hello,
I had a company out to clean/inspect my chimney. They found small vertical cracks in the clay flue tiles and gaps of missing mortar in the flue tile joints. They quoted me $8,000 to fix it with heat shield joint repair (one year warranty). The chimney is brick with a clay liner and exterior to the house. I burn dry wood in a modern efficient stove, so they didn't find much creosote. I'm wondering:

1. How dangerous is using the stove with the chimney in it's current condition? I realize it's not ideal, but with a clean burning stove is there much chance of a creosote fire? The company, of course, told me not to.
2. Is that joint repair a good idea? They said a liner would be a few thousand more.
3. If joint repair is OK, is that estimate reasonable? I'm in the Midwest.
4. I'm thinking about putting a liner in as a DIY project. I'm fairly handy and have a bunch of tools, but I've never done any chimney work. Is it doable, or a bad idea?

 

[stoveliker]

It is likely you need an insulated liner anyway per code and for safety.

I would put a liner in.
That is something that you can do yourself if you can get on the roof and work there safely.