If you call that 10% of gross rents you will spend $116,000 a year on property management if you were earning $1,000/month/rental (about 1/3 of your gross profit on 97 rentals.)  

Also, what if you spend thousands of dollars on a brand-new DADU, only to have the seller reaqcuire the house?

As long as you're not in a rush, we always recommend spending some time asking questions of DSCR lenders you might be looking at.

I do not recommend you spend a lot of money to get an attorney on this matter.

@Joe Villeneuve around 300K of equity in the houseSell the house, take the equity, spend it or use it on your next house where you are moving to. 

So I want to make it an enjoyable and comfortable experience but I dont want to spend too much

This reminds me of the discussion around pricing things at $x.99 instead of $x+1.00.EXAMPLE: $4.99 instead of $5.00Everyone "knows" that the price in the example is basically $5.So, why do billion dollar companies, spending more on marketing departments than everyone's combined income on this thread, STILL use the $x.99 pricing format?

The ways around that are to build a business around supporting their voucher and inspection program and spending no small amount of effort ensuring they are smoothly servicing your rentals. 

I'd use an approved underlayment.Pro Tip: If it's cheap, it's not good.....at least spend in the moderate range.

This means you wouldn’t need to spend time managing properties or building a team, which is perfect given your time constraints.