You also need to know, if indeed you are looking for a "condemned" house, that financing will be an issue. If, for example, there is no working kitchen (lenders define that as there not being a stove) you are looking at an all cash offer unless you and the property qualify for special rehab financing. And that rehab financing is not inexpensive.
Others have said it- work with a knowledgeable realtor, someone who will keep track of the market, scouts out properties for you, makes sure the value is there both before and after rehab, can give you cost effective suggestions as to how to improve the value of the property both short and long term.
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