Rates and Terms

The rate on the SBA 504 portion is set when the CDC sells the debenture
bond to fund your loan. The rate is then fixed for the loan term.
504 bonds are amortized securities. For comparable rates, look at
treasury rates.
The OSBDA portion has two options: 10 or 20 years depending on the
life of the asset being financed.
Collateral

OSBDA/SBA takes a subordinate (second Mortgage) to secure its 40%
portion of the financing, and takes a security interest in assets
financed. Other assets of the business or principals are generally
not required (unless the company is a startup or the credit is usually
risky or the asset being financed is considered a single purpose asset
or does not appraise high enough).