I found that often in literature that likelihood values are often used to compare different estimation method for the same model. And I got the impression that is the only way likelihood values are used.
However, I wonder what else we can say about the likelihood function. For example, can we compare two totally different models' likelihood functions? What's the minimum of the likelihood (obviously not zero)? What's a good guess about the maximum without going through into iterative method of estimation? (Can we build up inequality equations and claim boundaries for the likelihood function?)