Fannie Mae has the $1M minimum, but there are a lot of other lenders out there that do not have that rule.

Is there a set time or rule that banks use? 

There's no rule but I'm imagining you'd want to cover a month's worth of expenses if left vacant in January.

Look at the 50% Rule cash flow.  

I want to apply to an FHA loan.

I understand it will depend on the condition of the house but is there a general rule for that? 

Short REITs such as avalon that have large exposure to markets such as SF Seattle and NYC where rents went up so high to drive people to purchase but developers kept permittingNote analysis does not apply to sfh and non top 10 metro.

Someone correct me on this if I'm wrong but in your situation I don't believe a lender will count the potential rental income of your current primary residence if you're still living there while applying for a mortgage on the second.  

Heat is but a/c is notFollow the rules exactly as required in the property code before taking any action Send a certified letter requesting repairs and demand they be completed in 7 daysIf they are not completed, you can make the repairs and deduct from the rent or move to terminate the lease

There are additional rules for holding it less than 5 years (100% deferred gain recognition), 5-7 years (90% deferred gain recognition), and > 7 years (85% deferred gain recognition).- Any depreciation taken on the investment in the OZ is permanently saved and NOT recaptured if held for 10+ years.