My previous renters were relocations - either had sold their home and looking to buy another (low inventory so takes a while to find a home to buy) or moving here from another city and didn't know yet what neighborhood they want to be in, or alse building a home and need a place to live until it's completed.

Let's assume that the neighborhood is a C class and the median income of the city is greater than 3X of the market rent.Here are some of the considerations I've come up with so far:- Units are in need of renovation and capex is too high or not available- Unit quality is not the same as market - Seller is worried about losing tenants due to increase- Vacancy rates are high or filling units have been difficult- Rent increase would take multiple increases over multiple lease periods to get to market rate if seller is trying to retain the same tenant- Seller inherited property and just want to liquidate- Seller needs to liquidate quickly (financial burden, sickness, quick exit from land-lording)It seems like I might be missing a warning sign about a deal if they are selling with current rents that are under market; but again, this seems to be most of the properties I've underwritten.And in the same vein, what should I be worried about when purchasing a deal with under market rent with the intention of raising them after purchase. 

I would like to know how to read the market a lot better and learn how I can see wether or not a certain city is thriving or not, if where I purchase the duplex is thriving I'll just settle there and target SFH's there instead of moving out of state.  

Absent them, risk is controllable over time.I self manage a SFH in the Bay Area in a very pro-tenant city (some cities are a little less pro-tenant than others).

The City of Portland, and Multnomah County are more restrictive than most of the state for instance. 

I generally recommend if you're not going to buy a property in the city/market where you currently live, the next best place to look is where you have family (and presumably a place that you'll visit relatively often and easily).What is your price point and are you looking for turn-key properties or something along the lines of a "fixer upper", assuming you buy in Peoria or a similar priced Midwest market?

Jacksonville has been building at record levels and is/was one of the highest cities in the country delivering new housing units as a percentage of existing housing units.

One would be amazed at how many cities were platted between 1900 and 1940 in CA then the slow build out started..

The tricky part will be to get the the city to change your property's zoning to multi family (if it isn't already).

Looking to purchase a duplex, triplex or fourplex in Panama City and do short term rentals for summer months and long term through the winter.