I'll chime in. Currently, we do not use AVMs. By themselves, they are not evaluations. Also, in my state, we have to obtain approval from our banking regulator before we can use them.
As for the other issue, we primarily focus on the transaction amount ($250,000 or less; $1,000,000 or less, etc). For riskier properties or purposes (CRE, construction, etc.) we set a lower limit for in-house evaluations. We also differentiate between purchases and refinances. For example, in the last 18 months our policy was amended to require an outside appraisal on ALL purchases, regardless of transaction amount, regardless of whether residential or commercial purpose. We do not use LTV in our decision-making at all since we don't know what the value is until we do an appraisal/evaluation.