grammar/ meaning “To look at him, you'd never think he was 80!”

Question

Is the title sentence the short form of

(If you were) To look at him, you'd never think he was 80!

Likewise,

In other part of the country again, to give the example of Minnesota, you would probably pay only half of that maybe $400 or 450 a month.

Is the short form of

------ ,(If I were) to give the example of Minnesota, ----

As far as the short form is concerned, what do you think the full sentences are for the following examples?

1. Suffice it to say that they're having marital problems.
2. Say what they will about our cafeteria, I still think they’re the best tater tots money can buy.
3. After that, the golfer thinks that because a certain method worked for them...it will automatically work for everybody. And to make matters worse, they believe that there are a lot of absolute imperatives to the golf swing that all golfers MUST do in order to hit the ball effectively.

My guess is:

1. “If it” suffices to say that
2. “Though they” say what they will about our cafeteria,
3. “If they are” to make matters worse, ----(with a hint of irony ?)

Frankly, I really do not understand the sentence meanings of (2) and (3).

Answer 1

To answer your questions

1. To look at him, you'd never think he was 80!
   Means: When you look at the way he looks, you'd never think he was 80 - he looks a lot younger than that.

2. In other part of the country again, to give the example of Minnesota, you would probably pay only half of that maybe $400 or 450 a month.
   Means: If we again use Minnesota as an example for another part of the country, you would probably pay only half of that maybe $400 or 450 a month in such areas.

---

1. Suffice it to say that they're having marital problems.
   Means: To make you understand some of their issues, it is enough to tell you they're having marital problems. There is more but it is not important to this discussion.

2. Say what they will about our cafeteria, I still think they’re the best tater tots money can buy.
   Means: Some people have complaints about our cafeteria, but I do not care, their deep-fried, grated potatoes served as a side dish are the best you can get.

3. ...And to make matters worse, they believe that there are a lot of absolute imperatives to the golf swing that all golfers MUST do in order to hit the ball effectively.
   Means: Not only do they think certain methods work but they make even greater mistakes in their thinking when they believe the many ways they are told they MUST do when they swing.

Answer 2

This is either "an expression of amazement" or "an expression of utter disbelief at a truly unfathomable circumstance". I think it's the former and in that case it means "Wow!", "Amazing!", or "What do you know!".