How do you compromise with your spouse when there seems like no middle ground?

I actually have two specific scenarios that I need help with, any advice would be great

Scenario #1-
What do you do when your spouse wants to make a large purchase, and you just do not agree with it. there are many specifics to the exact situation, but too many to go into and I’d prefer to keep it broad since this situation comes up occasionally Let’s say this is something you do not need, there is nothing broken meaning you’d have to go out and get a new one…example: a tv. But the specific tv is on sale for a great price, but still would have to be put on credit.
How do you approach it without being the “bad guy”?
Also, what makes it more difficult is one spouse does not bring home any income, they take care of the child(ren), yet it would be their credit that is used since they have the best and only credit in the marriage.

Scenario #2— Naming a child!!!
What do you do when you just cannot agree on a name for a child? How can you even compromise on something like that?
One side has tried to compromise by using the name, but wanting to call the child by the middle name, but one spouse refuses and becomes irrationally angry and refuses to talk about names or even consider other names.
How is it possible to find a name and make both parents happy? It seems impossible at this point :(