If they are changing jobs, they need the new job first and you need to paychecks or offer letter with salary or maybe even the first two paychecks at the new job, depending on their level and income.Ask them about deposit and rent. 

@Jonathan Small Nice job on this find and completion.

My own personal experience is that a huge stressor has been lifted since I've stopped spending hours looking for and analyzing deals and my index funds/stocks are doing well (just hope it doesn't decline in value when retire from my W2 job). 

I feel like it would be great to trust a property management company on all of this, but it would be hard not to step in if you could do a better job at screening bad tenants (eg screening HUGE future problems).I initially managed properties myself, but now I delegate that responsibility to my business partner, personal assistant, or a property manager at my brokerage.Most PMs I know will send you an applicant for final approval and you can get on the phone with them and ask them questions

Also, focus on 2 years of job/income stability.Class D Properties:Cashflow vs Appreciation: Typically, all cashflow with little, maybe even negative, relative rent & value appreciationVacancy Est: 20%+ should be used to cover nonpayment, evictions & damages.Tenant Pool: majority will have FICO scores under 560 (almost 30% probability of default), little to no good tradelines, lots of collections & chargeoffs, recent evictions.

The article also fails to mention that overall transaction costs can actually be higher in countries where commissions are lower because the agent plays a different role, and due to needing to pay a lawyer for paperwork that agents complete here as part of their job (called a solicitor in Britain) plus VAT taxes and other closing costs need to factored in on top of the sales commissions, which we don't have here, overall costs can actually be higher even if commissions are lower. 

I like the idea of diversification of my investments and I love the strategy BAM has articulated: the focus on properties with below market rents in growing areas with jobs and good schools. 

Also, focus on 2 years of job/income stability.Class D Properties:Cashflow vs Appreciation: Typically, all cashflow with little, maybe even negative, relative rent & value appreciationVacancy Est: 20%+ should be used to cover nonpayment, evictions & damages.Tenant Pool: majority will have FICO scores under 560 (almost 30% probability of default), little to no good tradelines, lots of collections & chargeoffs, recent evictions.

I agree with @Jonathan Greene that the question is vague, so my advice will have to be as well.The short answer: MTRs are real estate, so just like all real estate, any place that can long-term-rent cash flow with increasing jobs/population can be a suitable site to purchase. 

A strong “Core 4” can make managing your investment remotely much smoother and prevent a lot of headaches.Also, as you narrow down cities, pay close attention to factors like job growth, population trends, landlord-tenant laws, and short-term rental regulations.Happy to connect with you, and good luck as you jump in!