Need contact for owner financing in Dallas

Hey all, who are y'all using for setting up seller financing in Dallas.  I have a great opportunity to buy here, but last year's 1099's were low (Covid) so conventional bank are telling me 'no.'  Seller has agreed to do seller financing for a few months until my next tax return gets done and I will be eligible for a regular mortgage again.

Anyone have a contact they would suggest for setting this up?  Also what kind of rates are we seeing for seller financing these days?