@Eli Tafesse
First determine if you are going to be a condo, single, multifamily, .... etc buy-hold investor. Once, you determined your niche, then focus on it. Find a local agent in your market, and ask him to add you to his daily listing for that niche/criteria in that market.
In the daily listing, it usually shows the rent rate for each unit for multifamily (I guess you might be able to apply the same principal to other niches). Stay on for 2-3 months to gather the rent rate data, in which can be used to compile statistic for rent rate.
The situation above will give you a few information: market rent rate, vacancy, and rent-ability. If most listings have vacant unit, then walk away from that market (it is just me).
To confirm how long the vacant unit is on the market or is there any demand.
Go to Craiglist or other ad sites, create a database (excel): let say you go on site on Mon
- Grab all available units on rent that were listed in the past 1-week
- Record all of them to your spreadsheet: price, address, # bedroom, phone #, ....
- Then on Friday or next Monday. Compare your recorded spreadsheet with the current state listing on Craiglist. I would presume a few of them are taken from your spreadsheet. Call each remaining rental listing to ask if the unit is still available
- After you called the landlord or Lister, If you think the rent rate is reasonable and most rental listing sits there for 3-4 weeks or more, you better off staying away from that market as buy-hold landlord. This meant the rental demand is not there and you won't strive in that market as landlord.