The disadvantage of cash is usually the time value of money. 

Advantages and disadvantages to each and the most important thing you can do is just get started.

My read is that 1031 and OZ funds are "two separate tracks" with each having certain advantages and disadvantages.

If you use that parcel as a comp, you have immediately shot yourself in the foot before you even get started.This thought process is the same in an urban environment, but the tract size is fractional (dollar for dollar) so the development costs as a percentage of project cost will usually drop (making it less influential).Sitting on land has its disadvantages:- Property Taxes- Insurance - Maintenance (grass?)

This puts them at a disadvantage when compared to the prudent person rule which drives the Duty of Prudence.

The advantage of a cash-out refi is a longterm fixed rate, the disadvantage is you immediately begin paying on the money borrowed and your rate will more than likely be higher than what you already have, making the current loan you have now more costly. 

And you can also get into investment classes that generally are too expensive to own directly on your own for many people such as large multi family, office, net lease, etc.The disadvantage is that you have to be able to vet the sponsor and feel comfortable turning over complete control to them.

From what I know, it is possible for investors to flood a market with capital which drives up pricing (over paying for property, incorrect appreciation assumptions etc) and/or can make deal terms much more restrictive (i.e. cash offers vs financing) which puts traditional owner occupied purchasers at a disadvantage in the short term however in the long term the market will correct for any errors and pricing will remain at it's market equilibrium.

You put yourself at a disadvantage perceptually and maybe actually if they hear something from you that indicates a weakness  or if they take action based on your recommendation and end up getting burnt and suing (yes I"m probably being overly Machiavellian today but I've seen it happen so indulge me :)Simply tell them the most important factor is they use an unrelated 3rd party called the Qualified Intermediary to handle an exchange and steer them to one. 

The disadvantage is that you lose the preferred lending of owning in your personal name.