There are certain neighborhoods that have had huge numbers of foreclosures and those neighborhoods are dropping in value. So you have to know exactly what you are looking at. There are probably over 20,000 neighborhoods in Charlotte so it's very hard to say... look here or there. If you give me your price range, and what you are looking for in a house, rental return, etc. I can recommend some neighborhoods. However, it is not that easy... and any agent the would sell you just "anything" is not an agent you would want to work with. Interview a few agents and talk to them. Give them as much info as you can and then when you get here... you can target in on the best buys based on your needs...and wants.
Well I see you are looking not only all over Charlotte, but all over the Southeast. I think you will see a much better result if you can focus in on,at least, a city.... first. If you are only buying for rental income your criteria are going to be much different than if you are looking for appreciation or appreciation combined with cash flow.
The houses you have picked out above all have their negatives. Glenwood is a busy street, Peachwood is in an area with a lot of foreclosures..., you can see that it is hard to pick a house from across the country... with no real criteria.
I would say that most of these houses would rent for between $500 - $700 a month. I do not think you will be able to offer half the asking price in Charlotte and have an offer accepted. If the home is bank owned then they have had their appraisals of the home and priced it pretty aggressively already. If it is owned by an individual then obviously they won't be able to take half as they won't be able to pay off the bank. Short sales are another story all together....but again they will require an appraisal before they take your offer.
If you are looking for appreciation and good cash flow, I would recommend you connect with an agent in the cities you are most interested in and then really work to refine your objectives. And they will be able to find you some areas that meet your needs... and then you can pick some homes.