What type of real estate are you purchasing in CA and most importantly  can you articulate the dispute you believe will rise to the level (with appropriate standing) to be litigated and benefit from being litigated in DE?

If I invest a multifamily through a Roth IRA, will I still receive the same tax benefits as I would with personal cash when I file my tax return?

You need to account for debt paydown, tax benefits, and depreciation as well.  2.

It seems the US has more tax benefits in Real Estate than Canada (I'm not sure) - How can I take advantage of it while residing in Canada?

This approach allows you to manage the property closely, benefit from homeowner loan terms, and potentially increase its value with improvements before renting it out.As you transition the townhouse to a rental, ensure the rent covers all expenses and provides a profit.

If you do not sell all units you can benefit from the capital gains tax.

It will familiarize you with the basic terminology and benefits.

I have came across HELOCs and HELoans but not sure which would benefit me best?

The biggest benefit of the LLC is in being able to have a sort of firewall between your companies and self.

None of you can personally benefit from something the SDIRA owns.