Many non-MLS 'referral brokerages' are under $100/yr and still allow off-MLS transactions or referrals from MLS deals.   

Do what it takes to make the transaction happen.

Payments made with a credit card or payment card and certain other types of payments, including third-party network transactions, must be reported on Form 1099-K by the payment settlement entity under section 6050W and are not subject to reporting on Form 1099-MISC. 

If you plan to work with international investors, then you need to have an attorney and a CPA that are well versed on the topic and can assist you and your investors with various questions and services that will be needed to execute upon such transactions.

It's typically a transaction between a sponsor/general partner and a pool of investors.

It would give you a nice introduction into the workflow and process of a transaction.

If unlicensed brokers are violating the laws--that is a scam.If they are misleading sellers, that is a scam.If they borrow $20 from their mom to use for EMD_-their mom loses:)Assignment fees are BLIND transactions.

Well, something that could be done would be to lend the money to the other LLC as a business transaction.

Are there any other ways that I can capitalize on this dual-company transaction for tax purposes? 

If you are just starting out and have no transactions under your belt, keep it simple.