Modeling 2nd Generation Vacancy

I'm working to build a sub-institutional multi-family model (think 10 units or less). I'm looking for guidance on modeling 2nd generation "Absorption/ Turnover Vacancy". See example below:

 Model has the following assumptions:

  • 4 units total / 3 units occupied at close 
  • $1K/unit/mo. on occupied units 
  • $2K/unit/mo. market rate
  • 12 month lease terms
  • 3 months downtime / (0% renewal probability) 
  • 36 month hold

Month 1 Rental Income is being modeled as shown below. 

In-Place Rental Income ($3K)

Plus: Market Rental Income  ($2K)

Gross Potential Rental Income ($5K)

Less: Absorption / Turnover Vacancy ($2K)

Effective Gross Rental Revenue ($3K)

The model effectively backs out "Absorption/Turnover Vacancy" during the three month downtime assumption for the vacant unit as well as for the in-place leases (upon expiration). I consider this 1st generation.

  • Logic looks at the Seller provided rent roll and says +IF(AND(Current Month>In-Place Lease Expiration Month, Current Month<In-Place Lease Expiration Month + Downtime), - Market Rent,0) 

The shortfall of the logic is it doesn't return vacancy projections following the initial market lease up and therefore Effective Gross Rental Revenue is widely overstated through the hold. 

What is best practice for modeling 2nd generation+ "Absorption/ Turnover Vacancy"?

Happy to dm model to those in the community who may be able to help here. Thanks.

6 Comments
 

Based on the most helpful WSO content, modeling 2nd generation "Absorption/ Turnover Vacancy" can be a bit tricky, but it's definitely doable.

First, you need to consider the lease expiration and downtime for each unit. You've already done this for the first generation, which is great. For the 2nd generation and beyond, you'll need to apply the same logic but with a twist.

Instead of just looking at the seller-provided rent roll, you'll need to create a schedule that tracks when each lease is expected to expire, based on your assumptions. This schedule should extend beyond the initial lease term to account for the 2nd generation and beyond.

Then, in your model, you'll need to create a formula that checks if the current month is greater than the lease expiration month and less than the lease expiration month plus downtime, just like you did for the first generation. But this time, you'll need to reference your lease expiration schedule instead of the seller-provided rent roll.

This formula should return the market rent as a negative number (representing vacancy) for each month that a unit is expected to be vacant.

Remember, this is just a general approach. The specifics might vary depending on the details of your model and the assumptions you're working with.

And remember, I'm Max the Monkey, your witty mentor. I'm here to help, but I'm not all-knowing. If you're still having trouble, you might want to consider reaching out to a professional or someone with more experience in this area. They might be able to provide more specific guidance based on your unique situation.

Keep swinging through those financial trees!

Sources: General Vacancy Deductions

I'm an AI bot trained on the most helpful WSO content across 17+ years.
 

This is a great question and I see this issue come up when reviewing multifamily acquisition/value-add models -- DM me to talk thru this but in the meantime here are some of my thoughts.

As you know, modeling rental income off of the unit mix remains convention when assessing acquisition opportunities -- and 99% of the models out there follow this methodology.

That said, I've found (maybe) three models that allow the user to model rental income off of the rent roll: in other words, by unit. Still, maybe one is setup to account for more more than one "Lease Generation".

In reality, once the multifamily property is acquired, distinguishing between Contractual Rental Income, or rental cash flows from all in-place lease agreements and the corresponding "In-Place Vacancy Loss", and Pro Forma Rental Income, and the corresponding "General Vacancy Loss", is crucial to building out your asset management model which essentially feeds into your annual budgets. The problem is this exercise is predominantly solved thru the use of platforms like Yardi.

Therefore, instead of paying thousands of dollars on a full Yardi subscription, I built my own multifamily asset management model for a 75 Unit multi located in South Florida that underwent a $50M Repositioning which included re-configuring / combining 86 Units into 75 Units. I built in the logic to account for up to 5 Lease Generations (since the asset's WALT is ~2.5yrs) so the model is able to break out contractual / pro forma vacancy from absorption and renovation down time.

Like I said, DM me and i'd be happy to talk thru your questions.

 

If you’re modeling multi family rents off the unit mix, do you always use an annual model for these purposes and an approximate 50% loss to lease each year? Wondering how you model off the unit mix for a monthly model while still handling the varying expiration dates throughout the year accurately for the purposes of rent increases. My thought would be this is only possible through modeling off the rent roll

 

*I never model rental income off of the unit mix for properties we own. I model rental income off of the rent roll. 

*Whether or not own we a property, I don't incorporate Loss to Lease in the pro forma because I model off of in-place rents so my P&L starts at "Potential Rental Income" (PRI) while yours likely begins at "Gross Market Rent".

*Yes, if you're looking to model monthly cash flows you would not use the unit mix approach.

 
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