As explained in this article, seller financing works best if you understand the needs of the seller.https://www.biggerpockets.com/blog/seller-financingReally dig into this topic and ensure you understand it and are prepared to use it.

You started by saying that you have Local bank relationship. 

The thing I'll be changing is the financing I've been doing with a local bank, which has been a bit slow and cumbersome.

If they do, your best bet is a local community bank that funds these types of properties.Another option is a private lender but that money will be pretty expensive, as mentioned 10%  + 

Quote from @Samuel Coronado: Quote from @Jordan Moorhead: You can use local banks and there are national lenders.

Just a little additional risk that probably wasn’t mentioned when they were explaining “infinity banking”.

Mainland banks can not finance in PR. 

He may accept a lower rate than bank financing.

Because you own an interest in the property, can you short sale it to another LLC, through working with the bank?  

Would love to connect and explain some possible scenarios based on your criteria!