I pay about 5K for my three-flat that is about 430K in the city of Chicago.  

With the rent range of $500-700/door for MFH, that is the crew who are typically one flat tire away from not paying.  

I've heard that diversifying geographically and investment-wise (not all SFR, not all 4-flats, not all commercial) is a really good way to invest since you can weather lots of different storms.

Getting a response from the owner is another matter altogether.  

So, in a flat or declining market, most won't by the house.Most won't have the money or the improved credit to buy at the time of the option. 1-3 years is usually not enough time.

Most flatly refused , and told the banks to back off.

This is a case where the seller tried to take advantage of someone not from the area, flat out lying about the value.  

Have you found that after you posted the notice they became stand-off-ish and decided to stop paying their portion altogether? 

I've got some flats in west London which I self-manage (actually from where I live in Norway). 4 websites which I found were very helpful for learning more about UK property investment are:1. www.thepropertyhub.net (similar to Real Pockets but UK based and on a much smaller scale)2. www.propertytribes.com3. www.propertygeek.net4. www.thepropertyvoice.netHope you find these useful - I'm sure that you will.Have a great Christmas and New Year. 

look up house hack.. if you can swing it buy a 2 flat or 4 flat... use your FHA loan with 3.5% down and build your number of doors instantly ... as you get stronger you can move to another place and you have a very nice asset.