Maybe one day they will convert bitcoin maybe at even higher fees 15-20%,25%?

Investing in features like high-end appliances and modern designs yielded a higher ROI.

In your case since your properties are paid off, I don' see any reason why you would use a higher interest HELOC instead of just doing a cash out refinance.  

Additionally, your brother would inherit your cost basis for the gifted portion, potentially leading to higher capital gains taxes if he sells later.

If you aren't paying cash and are doing owner occupancy you may be able to use FHA instead of Conventional with a higher down payment. 

Keep in mind a HELOC rate will be much higher because of the CLTV and risk.

Crypto is a volatile asset, but the rewards are magnitudes higher than any other traditional investment.

That said you can greatly alleviate that with good screening, and the higher price point that these types of units can demand should help filter out the deadbeats.

Firstly, it often generates higher rental income compared to long-term leases, particularly in desirable locations or during peak seasons.

@Denise CarringerMy preference is to go local - some community banks offer this type of service or local escrow companies, which is what I found, because they offer a higher level of service than most national.