To Lend or Not to Lend

I have been presented with the opportunity to Lend to an investor on a property she owns free and clear.

"I am looking for a short term 90 day or less loan secured by the property for rehab costs of $15,000 @ 20% flat fee interest on a property I own free and clear. My goal is to finish the work in 30 days or less and then list it and sell it. We will do a promissory note with personal guarantee and a mortgage note lien to secure the funds you the house.

Purchased $190k

Repairs $25k

(I’ve put $10k of my own money in repairs already)

Selling for $279k"

what do i need to consider? Any tips?