In buying any property, you cost basis is the main factor and the lower your financing cost the lower the overall price of the project.  

If you are in a buyer's market, you might have to suck it up for an otherwise good tenant; if you are in a seller's market, you might consider raising his rent to help with the aggravation factor.

Would you happen to be familiar with the exact calculation that lenders use for the DTI calculation when factoring in other properties?

If they don't understand cap rates and how to use the factors that drive cap rates to determine value they may just be shooting from the hip.

Sounds like I should definitely factor in more hold time and keep an eye on the exterior work.I imagine you can put off landscaping and curb appeal though ;)

Traffic/congestion may be a factor.  

I've ran the number a million ways but maybe there's something I'm not factoring in. 

I'm a newbie myself but the main factors are the purchase price and neighborhood rents.

I know that each area is different and it's impossible to isolate one factor.  

HI Tom,I've done plenty of these on the lender end and investor end as well.If you go the FHA route which is the least down payment option you'll only need 3.5% down and will need to adhere to:- min 3 months cash reserves based on the proposed monthly payment- gross rents on all 4 units X 75% factor must be equal or greater than the total monthly payment of the property (PITIA - I found out this not include HOA in this formula as we had a fourplex with a HOA once too).