I don’t believe 10k is sufficient enough to really do a deal on one’s own for the most part.

Given that the borrower had given us sufficient time to complete the loan processing and clear all title conditions, we were able to arrange the financing with one of our multi-family lenders at a rate that was actually lower than the prevailing rate when the borrower initially contacted us.

You don't need anything significant drawn up for the loan agreement either, a verbal agreement may be fine or just an email exchange can be sufficient (you could sign if you realllllly wanted to). 

Focus on quality, not quantity.

If the person who emailed you has the authority to release the agreement, then I'd say the email is sufficient 

If you do then most certainly do a 1031 exchange into another winner of a property or even better do a cash out refi, provided that the debt load is sufficiently covered by the cash flow from the rental.

FHA 3-4 units has a self-sufficiency test which can be difficult to pass in higher priced markets where the rent from the other units needs to be greater than or equal to your total housing payment. 

So look around, interview other STR owners so that you have sufficient information.

Hi Rob,If you believe the HELOC will be sufficient for the purchase & rehab, it could make sense to use the HELOC given the interest rate is lower than a hard money. 

As long expectations are managed, either route should be sufficient.