There could be some restriction about this but I don't personally buy properties to flip, I currently only buy and hold.

We've been near 100% occupancy since the restrictions for vacation rentals were removed. 

An overlay is a requirement set by the lender that is more restrictive than Fannie/Freddie guidelines. 

I would definitely find out from the local municipalities any restrictions or requirements that they have for landlords.

I'd heard of similar restrictions with Lending Club and Prosper, but not for ther real estate crowdfunders.

Hi Pablo,Should there be no HOA restrictions on short-term renting, I'd be happy to help look at your possible short-term v. long-term rental income earnings.

I keep reading that to refinance a rental property though is much harder: higher interest rates, more restrictions, etc.

This usually restricts you to properties where the seller has no debt on it...and, you have to convince the seller that it is in his best interest.  

If so, there are restrictions regarding your ability to substantially improve the property. 

Syndications are available where you can invest in a loan as a partial owner of the note.There are a number of real estate crowd funding platforms (including one I own) that allow accredited investors to easily see, analyze, evaluate and invest in mortgage loans online.There are also "blind pools" where the investor puts his money into a limited partnership type structure that invests in high interest loans - in these the investor does not know before investing the makeup of the loan pool, so he's totally reliant on the general partner.The big thing for the passive investor is that he is no longer restricted geographically; he's free to find the best yield vs risk opportunity available.