Also enabling them to rollover IRAs and old 401ks into a Solo401k.

Congrats, guys, and thanks for providing quality content and extracting all the details out of this deal. 

Two huge points you are not mentioning: the up-to-$50k loan that can be taken from the SD401k for any purpose, and the fact that the SDIRA requires an LLC to enable checkbook control (which is the only way I'd invest due to convenience, speed, and lower custodial costs), whereas the SD401k does not need an LLC.

Is here a way to extract the cash out of the company and take the distribution, pay the income taxes BUT avoid the 10% excise tax?

Several moving parts and complex (at least for me), so bear with me:Brother (J) owns home where mother (H) lives, has a cheap mortgage, but would like to extract his equity for other investments.

So you need to extract what you need in 24 hours and store if the short video coverage is not enough (only limitation which has not been an issue so far). 

This will enable you to know what you'll make (% wise) so you will be more consistent.  

If you zoom in with this enabled, you'll get the tax parcel number for any property.

It also allows you to set multiple passwords that enable different cameras - so everybody can see the parking lot and laundry room, but maybe some areas are more restricted (IE, a tenant can see their own entrance only).

If you then create 25% equity, so your all-in cost is 75% LTV you can extract 100% of your funds with no seasoning.