I am in one of the higher tax brackets and could be saving around 40k~ a year on taxes with this.

In that case you might save taxes building with them.

[1]    You might want to think about opening 2 FDIC insured savings accounts that have no fees.

Typically they charge a percentage of the amount saved. 

Now 3 of the 5 taxing authorities give a credit for doing them on time which can be as high as $150 savings for me each month and I am not sure I would get that using Avalara.

Interest income is interest income, unless you decided to roll some of the current cash into a self directed IRA at which point your interest income would be deferred for a later time and allow your funds to grow tax free.

Fannie/Freddie (Conventional) loans aren't just about rate and transfer taxes. 

I have sales reps that know me, free delivery, net 90 billing, constant product updates a bullet proof warranties.

For instance, many tribal lands are exempt from state and local property taxes, which can obviously lead to significant savings.

They will save you time and money.