Property development deal

Assalamu alaikum. I have a question in regards to the permissibility of a property deal i have come across. A property developer looking to build private and serviced accommodations is offering a couple of deals

  1. if paid in lump sum a 10% annual return on purchase price paid monthly while they are developing the site (expected to be 4 years). After completion rate will drop to 6%. They are calling this rental.

  2. if purchased in instalments over 4 years, a 6% return will be offered once build has been completed after 4 years.

Would any of these 2 options shariah compliant?