@Christopher Mooney- HELOCS are relatively  generic  from one lender to another ...check terms ...margin...indexes ..maximum ltv and cltv  allowed ...interest only payment  terms ...overall terms ....prepayment  options .   

Just red flags all around.I have been investing consistently into the S&P 500 and other “safe” ETFS/Index funds for the past 3 years now.

Once you have those answers you can calculate your return on investment (ROI) and compare that to potential returns of other investment vehicles like index funds and bonds, then decide whether that ROI suits your long term goals.

This is similar like holding stock index , if market going down, what would you ?

There's no need to harp on those aspects and besides, I'm here on a real estate investment forum soliciting advice real estate investing, not stocks, bonds, index funds or any of that other boring stuff where you have virtually no ability to improve the value of an asset Sooo, with that little diatribe out of the way...Per my understanding, I've outlined below how the process works for investing in Real Estate using a self-directed 401k.

And there are several index funds to choose from.2.

If it was 100% guaranteed and hands off then you wouldn't be able to get outsized returns compared to say index funds or treasuries.As for $225k that can get you a duplex in a pretty good area here that is mostly turnkey.

While it's there, he invests it a balanced portfolio of 60-70% broad based index funds and the remainder in domestic bonds.Then, with the other half, put 25% into syndication deals, 25% into dividend producing stocks, and 50% he dabbles with in things like HML, house flipping, etc.

@Brandon Miller one way to know this is not the right move is that you can simply make more money by making a 20% down payment and putting the rest of your money in an index of the S&P 500 as that returns on average 10% per year and your mortgage rate will certainly be less than that. 

I am passively buying indexes through my 401k, but I am sort of worried about the state of the stock market, to be honest.