Define your goal and criteria and buy below FMV. 

How is market value defined?

Building systems is all about defining, documenting and executing the actions required to deliver your product, in your case a beautifully rehabbed home, to the marketplace.So, for example, let's say there's a certain way you walk through a house that you're considering purchasing.

But just make sure to ask lots of questions because it doesn't appear that this is a major part of their business or a core component. 

Are their values defined and are people held accountable to them? 

Investopedia defines occupancy fraud as a scheme used by investors to qualify for higher loan-to-value ratios and lower out-of-pocket costs on purchases, in addition to lower mortgage rates.

Buying an older house (built in 1959) requires more replacement components than anticipated.

It would list all of the major components of a home, along with their estimated associated costs per unit.

It's a fun, hard to define (and unfalsifiable) word that is hard to challenge when the card is pulled.

That being said if you do decide to go the partnership route you want to make sure to clearly define everyones role, responsibilities, capital contributions, loan guarantor roles, decision making authority and exit from the partnership if someone wants out.