model

assocations.rb

$> rake g migraiton add_institution_id_to_users institution_id:integer
$> rake g migration add_user_id_to_loans user_id:integer
$> rake g migration add_loan_id_to_quotes loan_id:integer
$> rake g migration add_institution_id_to_type_of_loans institution_id:integer

models/institutions.rb
class Institution < ActiveRecord::Base
    has_many :users
    has_many :type_of_loans
end

models/user.rb
class User < ActiveRecord::Base
    has_many :loans
    belongs_to :institution
end

models/loan.rb
class Loan < ActiveRecord::Base
    has_many :quotes
    belongs_to :user
end

model/quote.rb
class Quote < ActiveRecord::Base
    belongs_to :loan
end

model/type_of_loan.rb
class TypeOfLoan < ActiveRecord::Base
    has_many :loans
    belongs_to :institution
end