Do you mean the appraisal itself? I do have the appraisal itself, but I do not know what survey you are talking about or what the "communication of the subject" is. Bear with me, I'm not used to all the terminology yet.
You are asking appraisers on the forum how long it takes them to complete their site inspection. You are surveying them for their answers; that is the survey I reference. You are taking a survey.
The subject of the appraisal is the house. The report communicates the appraisal results. I'm presuming that you are asking about the time the appraiser spent at your house because you think it was not long enough (this is implied in your raising the question). I'm asking if you received the appraisal report because, regardless what we say here (10-min, 20-min, 30-min, etc.), that is only half the evaluation equation. The second half is how adequate was the report's description of your house and were there any significant factual errors or omissions?
If the appraiser was at your house for 12-minutes, and the report accurately and factually describes your home (the improvements), then 12-minutes was sufficient time spent at your house for the appraiser. If there are significant errors (and I don't mean off by 50-feet area on a 1,850sf home): like, you have 5 bedrooms and the report indicates 4, or you've remodeled your kitchen and the report makes no mention of that (likewise, you have some needed repairs and the report makes no mention of that) then one could say that 12-minutes was not enough time for the appraiser to inspect the property.
So....
1. You are taking a survey of appraisers here; you have feedback on how long it takes some of us to do an inspection.
2. The appraiser for your appraisal was at your house for 12-minutes.
3. You do have a copy of the appraisal report.
Question: Is the description of your home (the improvements) factually accurate?
If so, 12-minutes apparently was enough time. If not, it could be 12-minutes was not enough time (it could be the appraiser is incompetent no matter how long he/she spent inspecting your house).
Some things that are significant to the owner are inconsequential to the appraisal process. Condition, size, configuration, upgrades, needed repairs, view, are things that are typically significant.
Were these things factual and accurate in your report?