It would depend on what's in your new lease.

Vacancy can be 0-25% depending on turn over and what month they move out.Maintenance depends a bit on age of home but I would use about 0.1% to 0.2% per monthCap Ex depends on traditional (.5% a month) or private money (1%)Sales Expenses:  6-8% for closing and realtor plus about 2-4% for holding costs

I think it depends more on what you'd do with that $40k than the money itself. 

Spencer Hsu I offer full real estate services in Indianapolis and believe I can assist you with your first duplex depending what your price point is.

It depends on where your location is, in downtown LA, you can't build anything under 150/sf.

Close the deal(through the title company or an attorney by way of double close or assigning the contract- it depends on the laws in your area) and collect your check.

I've considered it but have not executed.In regards to the heloc if I understand things correctly you will not be able to take out a heloc on a investment property but simply a loc or a blanket/commercial loan depending on the financial institution you decide to approach with the situation.

It all depends on the plan document and the fee schedule of the provider. 

From what I have read so far, it seems to vary as to how many months of reserves we need per property, depending on with whom we refi.

If you were to go that route, you could likely borrow the funds immediately (well within your 48 hour timeframe) after signing the loan documents, but this will depend on the actual documents which can vary from one provider to another.