Putting together an LOI for Fitness certification business

Hello searchers - I am working with a seller on basic terms for acquiring a business focused on holding courses for an internationally recognized certification programs. The courses currently taking place in SE Asia. Business is doing between 400K -600K in EBITDA.

The seller wants 30% cash upfront and is looking for seller financing for the rest. This seems very aggressive but curious if there is a structure that can work for the right multiple.

Has anyone looked at something in a similar space? Any insight on multiple, structure and considerations are appreciated.