Based on my experience of running properties, even if the build were to cost you as much as $600k but you could generate $125k/year, you'd be very happy with that investment. 

House Hacking a primary residence is the best way to generate wealth so I always recommend that as the next move. 

From day one I treated my involvement in real estate as a real business.This means, I had an advertising budget, a lead generating and follow up process, a back end process and money source and above all an experienced mentor.  

Which is also one of the 3 fundamental needs of a business most often (customers, product/service, place of operation). 

If you are searching for offmarket, you can network with local wholesalers, and also use something like dealmachine to generate leads.

If not, understand the risk of taking equity to generate more equity based off your ROI.

During this time you are not generating any return from the money invested in the ADU.

On a rental that’s not generating income is it any different book keeping wise then you would for a rental that’s is making money Or what are good things to know or learn Thank you !

I had no money to put down on any properties, so I learned (a lot) and put in a lot of hard work and effort to get some properties under contract.Initially, I had no clue what I was doing, but I had the help of some people (and I appreciated that)I made mistakes that cost me around $30k (lost a deal due to my ignorance regarding title and escrow)The good news with wholesaling is that it doesn't take a lot of capital upfront, and you can start talking to sellers and learn about the industry in general.The other good news is that you can without a doubt generate revenue quickly if you do things correctly (having a good TC / title / escrow connection that keeps deals moving on the backend)That said, there are a few points that I've come to live by:1.

regarding roofs  pray for hail storms and then replace .. in those type assets that are really priced for cash flow.. values will rise only when rents rise.. as non of them will ever go owner occ.. at least that is generally what happens with this type of housing.. the value play is the tenant pays off your home and your home generates enough cash flow to break even at best and feed it a little bit over time.. then at the end of your mortgage term 30 years you now have say 2 mil of paid for assets the real money is made on these assets cash flow wise ONLY if you pay cash IMHO