However, if it's truly one of those communities that has very high crime and difficult to attract any descent tenants, it can lead to disaster.

Its the best way for anyone to get started IMO.Will add that in todays market you might need to put down more than the minimum 3.5-5% in order to not be cash flow negative.

If you could stomach the negative cashflow or get creative holding is not bad.

I'm talking $100 to now $450 per lead in my area.

Let’s project realistic expense estimates via the 50% rule:$12k rent / 2 (50% rule) - $19332 P&i = negative $13332/year or negative $1,111/month.  

For instance, if the neighboring unit has a shut-in chain-smoker, or the house has railroad tracks behind it, it is definitely better to let a lead know and lose them than to not disclose, upset them and lose them (after they leave a nasty review).I'd agree with Jonathan that even late complaints need to be taken seriously, and barring some obvious malfeasance, I would just take the word of the resident and fix the issue.

Agreed, and in many cases, insurance is destroying cash flow if not pushing it into negative territory. 

I have a lead on multi-family deal that should cash flow at least 1k/month, probably more.

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.

One lender I spoke to said they can do DSCR on it 7-8% no prepayment and up to 90% ltv which sounds great because then I don’t really need to refi right away because not puting the 20% into it I’m find puting 10% if it can cash flow a little and on to the next so they are in the lead for now.