It appears from your facts that you may not be an independent contractor in the eyes of the law; that is: own time, own resources and other clients. Not work for anybody else (like a lawyer or any business) equal employee . If employee must be paid next paycheck or three days whichever comes first and triple damages if not receive. Attorneys fees recovery is mandatory in wage claim. Can follow up with Arizona wage and hour board.
If your boyfriend did not sign the loan documents to be liable on the loan and note did not write check for a loan payment or sign a personal guaranty then he will likely not have the evidence necessary to satisfy the statute of frauds which requires real estate transactions to be in writing. This "writing" does not need to be a contract; it can be a check or receipt but he needs enough evidence to create possibility of a contract. Otherwise, his payments and work could be considered as rent....