Source for identifying home owners and getting tax records

[Donny Smith]

I my name is Donny Smith. I'm in the Detroit, MI market. I and my wife are newbie investors for about a year. Our focus has been on wholesaling. We have sent Direct Mail yellow letters. Have gotten a couple of nibbes, but no deals yet. On of the concerns I have is getting good comps. I have access to MLS through an agent. I have gathered comps for subject property. Not sure how acurate they are. Not able to get feed back from agent on how best to preform Comps. Should I look for a more investor friendly agent?