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Unfortunately, the answers to both the asbestos siding and outdated wiring questions are YES, the value is most likely going to be negatively impacted, all other things being 'equal'. The siding and the wiring are a form of obsolescence. Sub-standard electric CAN be a hazard, and asbestos has been shown to cause serious health problems in many cases.
(Having said that, I spent many, many years as a child romping around grandma's basement, in which every pipe was insulated in asbestos. No negative health effects that I am aware of so far......knocking heavily on wood......)
In my neck of the woods, the very mention of the word 'asbestos' causes all sorts of panic, and in many cases, serious misunderstanding, particularly within real estate transactions. Some will run for the exits.
I highly recommend that from the start, you target for the right 'kind' of buyer, if at all possible. (Construction people, for example, deal with asbestos, lead paint, and other hazardous materials all the time. Disclose the conditions upfront and target for an 'as-is' buyer. But, do a little homework first. There is lots of information online regarding asbestos in existing homes, and possible courses of action.)
As far as determining what the actual impact to value will be, are there other homes with the same kind of siding in the area/neighborhood?
You may have local / state codes that specifically address existing asbestos.
Generally speaking , the cost of upgrading the electric to current standards, and the cost of replacing OR encapsulating the asbestos shingles are taken heavily into consideration.
Consult an experienced, qualified appraiser! This, in my opinion, is not considered a typical appraisal assignment, but complex. Ask up front if the appraiser has the qualifications to do this type of an assignment.
Hope this helps!