@Ben Leybovich  This did get out of control and was not my intentions.

I am a little bit of a control freak ;)

I have been researching "Checkbook Control" Solo 401(k)s here and on the web... 

Many Solo 401k participants invest their Solo 401k directly into real estate because an LLC is not required for such an acquisition nor is it required to have checkbook control over your Solo 401k funds, unlike with an IRA LLC.

so controlling the remodel cost I think would be the key to success there..

Regular landscaping/yard care (mowing,edging, trimming, fertilizer, weed control) will be provided by_______________________.For allTenants:a.    

@Bil Casimir  you can "help" your Mom's IRA BUT you can not accept a dime for doing so, you can not benefit personally in ANY manner, nor can you manage her IRA or IRA/LLC for the reasons @Dmitriy Fomichenko  stated above.In general though, your Mom's SDRA can and may want to setup an IRA/LLC for which she can play with Real Estate and manage her own LLC, on behalf of her SDRA, as needed for asset protection.You mom's SDRA can invest in another LLC so long as there are no disqualified individuals in the same LLC with a controlling interest.With all that said, if YOU want to play in her retirement sandbox...then she may be able to form an S-Corp on her own, do a reverse IRA Rollover to a new 401k sponsored by her S-Corp and then loan another LLC, or fund her an LLC that you and her are part of, or just your LLC, the money for the Real Estate...whichever way you all feel comfortable with.This is very important to get right...so don't hold weight to any forum post or opinion, consult the professionals in your local area for further guidance.

Remember you don't have to own a property to control it.

You can control debt, to a degree, by finishing faster.On the other hand, if you are doing a particularly risky flip, with an uncertain timeline or cost, a 50/50 partner can offset some of that risk.

Since we do low income and self manage, we need to be nearby to keep things under control.