In fact, many of our clients will concentrate their cash into one of the purchases and even purchase it with no debt if possible. 

If you have no idea what is going on with this capital call, then the bias should be "no" until you understand what is going on and believe that is the best possible use of your hard earned cash. 

Negotiation tip #47, make it as simple as possible for the other party to accept your terms.

American Banks (like BofA and Wells) actually did lend in CR pre-2008 but that possibility disappeared after the crash.

@Chloe Salcedo why aren't you focused on working with your sibling and learning as much from them as possible?

Are they doing everything possible to expose properties to the broadest possible market?

That level of diligence isn't possible with human effort or even traditional data processing techniques.I would like to expand to investors in the future but this technology is very new. got it also commerical Brokers I suspect would be a target for you.. 

BiggerPockets also has a calculator to analyze deals, and I highly recommend you start this as soon as possible, even if you are not ready to buy.

It can be done ethically, but you need safeguards to confirm mortgage & possibly property tax payments made on-time, as well as insurance with you protected.- Also, you need a legal way to take back the deed if buyer defaults!

@Johnny Lynum we did offer them an aggressive cash for keys amount to get them out as soon as possible.