Once these type investments develop a history, I can see a market similar to peer to peer lending where default rates become standardized and known.  

The sponsor is likely suggesting that your monthly cash-flow will be shielded by depreciation and you will likely see your 'tax hit' when the syndication disolves which in industry standards is likely 5 to 7 years.

Some of your requests may fall outside this manager’s standard practices, and customizing services for each client isn’t practical for most PMs.

And if it's a high amount, would you be better off just using that as a downpayment and get a standard new investment loan?

I am happy with them, I think they bring up value to investors, still I believe many of their deals don't meet my standards ( do your own diligence and run your numbers!). 

Fortunately I have all the standard contingencies.I also question what is a fair price for insurance.  

------------------------------------------------------------------------------------------------------Recommend you first figure out the property Class you want to invest in, THEN figure out the corresponding location to invest in.Property Class will typically dictate the Class of tenant you get, which greatly IMPACTS rental income stability and property maintenance/damage by tenants.If you apply Class A assumptions to a Class B or C purchase, your expectations won’t be met and it may be a financial disaster.If you buy/renovate a property in Class D area to Class A standards, what quality of tenant will you get?

It took new construction costs from $800-2500 down to $325 / SF and instead of 2 years it can be done in 8-12 months (design, permits, fabrication, shipping, and erection) depending on how much homeowners customized the standard plans. 

Did you use standard offer contract for your jurisdiction? 

One of the others is 200 lots plus with townhouse lots which are popular.and the 3rd one about 110 lots its a land assemblage so layout is not standard.