Most efficient source to pull funds from for a down payment?

[Mike Levene]

I currently own 3 units and looking to add to my portfolio in late spring/early summer of 2025. I'll be in the market for a duplex/triplex in the $400k range that I will owner occupy and use a 5% down loan. I have some of the required funds in a HYSA, but will most likely need to draw from another account and I'm curious which method is the most efficient in terms of taxes/capital gains, penalties, loan repayments, etc.

Based on my previous transactions in the market, I estimate ~$45k cash to close: $20k for the down payment, $15k for closing costs and prepaids, and $10k of starting reserves. I have gotten a seller's credit for my 3 existing units but to be conservative, I will assume I am paying full closing costs here.

At the moment, I have ~$25k in a HYSA and expect to save another $10k from my W-2 before I start putting offers in. That means I have roughly enough for cash to close, but no reserves left over. FYI I do have plenty of reserves for my other units already, but would like to keep each property separate.

My question is, where should I draw funds from to pay the least amount in penalties, taxes, loan interest, etc. from the following sources I have available:

- 20 year 401k loan for a property
- Sell a piece of my stock portfolio at 15% capital gains tax
- Take a HELOC against an existing property
- Private money loan from a trusted partner I have worked with before

Alternatively, I could pool the reserves for all my properties to ensure I can cover anything immediate and know that I could always sell off a piece of my stock portfolio if needed and have the funds within 3 business days or set up a HELOC and only draw from it if needed.

Appreciate any thoughts or what you have done in the past.