I'm looking for a new source of investors who are in the business of funding these deals.  

Airdna is a good resource and tool, but I wouldn't rely solely on that platform for data.

I'm happy to answer or confirm any tax/accounting questions if you'd like Just to clarify what Steven is telling husband-wife business owners,If you have not created a business entity, you are operating as a partnership (not a sole proprietorship) and should file a partnership tax return.

They claim to charge in the "high 4 figures" - one web source says it's $4800 - to join their group and get access to their network and resources.  

The source of the loan does not matter.So yes, if you borrowed $100k and used $50k to buy B and another $50k to buy C - you deduct half of the interest against B and the other half of the interest against C. 

What are the best sources or methods you use to accurately set rental rates in your area?

Go direct to seller, learn to source your own deals and you will be successful  

I prefer to source all my deals off-market, which allows me to find properties with less competition and negotiate directly with motivated sellers.

My humble advice to anyone attempting to do creative finance is:Creative finance is for experienced investors who have access to capital if anything goes wrong.Learn the lawsDon't use a contract "off the internet", laws vary by state and are also regulated on a federal levelLearn the financing techniques correctlyDon’t skip parts of the processDon’t ever do a “kitchen table” closingUse the proper deedAn attorney can help you with the legal work, but the rest you are on your ownYour guru will not bail you out“Investing” in someone else’s deal by providing a small 2nd loan so the “investor” can pay for “cash to the seller” and for “closing costs” so he can do the deal is a very bad planKnow what problems can ariseLearn the responses and solutions to problems before they are neededKnow everything there is to know about Title and what that meansKnow who a "protected class" individual isLearn the "back doors"Learn human natureUnderstand timelinesUnderstand regulation enforcement (some of these "mistakes" have a 10 year statue of limitations ( they can charge you 10 years AFTER you do the transaction) and carry hefty fines and possible imprisonmentThe court doesn't accept "I didn't know" for an answer"Know that the source of the lead plays a serious role in some states and federallyKnow how much of a "profit" pushes the boundaries to invite an investigationYou can be sued by the seller if you don’t do things correctlyYou are automatically at fault if an investigator or attorney or regulator gets involved.

In my instance, my wife and I are currently on the title and would be the sole members of the new LLC.