I know of 3, 2 that I work with the most for my clients, but what I have found is the inherent issues that come with them.
There tend to be two big issues with 100/100 lenders that I have seen, the first is working with/being a borrower that is okay with the heavier lift that these types of lenders require. For a group like this, even with experienced investors, you have to prove that you have that experience which can take some time, and on top of that they tend to need a certain experience threshold within a certain period of time (usually 3-5 years). Those factors, plus the work needed to underwrite something like that, tend to make them trickier than say, a 90%/100% lender.
The second thing is ensuring that the values that they are operating under will work with 100% financing. Most 100% lenders will lend at 100% UP TO 70% ARV, which is tough to secure. Not only are those deals tricky, but you also need an appraiser to agree with the values needed to make a deal work, which, lets be honest, can be a bit of a crap shoot.
I know of a few doing it, but preparing yourself for the work of getting it is usually tricky.
Otherwise, **Following** to see if there are any others out there that I don't know