ADU in Sunnyvale CA cost

[Harry Zhang]

Hi everyone!

I'm (26M) super new to real estate investing and this is my first post ever so thank you for any help! Because I value your time I wanna keep it concise

1. I bought an 3/2 SFH in Sunnyvale in 2022 on about 6400sqft lot

2. The home is about 1300sqft

3. I am a software engineer making about 250k+ a year

4. I have about 150k in stocks which are liquid 

5. I currently rent out one of the rooms in my house for $1100/month, I use the other two rooms

6. I have been thinking about adding an ADU, probably a 2/1 or a 2/2!

7. Doing research online, it seems the price of an ADU might be around 350k

8. I'm pretty handy, I demolished the kitchen myself, put down flooring, and electrical wiring and all that. 

Questions

1. Is building an ADU a good idea right now, or ever in this area? At the cost of 350k, it's quite a lot and I would have to borrow about 200k. How should I think about this?

2. Could I hire someone to do the foundation, utility connections and framing, then do the rest myself to save money? Is that a good idea?

3. Are there any alternative investments you would recommend me? I also have a 300sqft detached garage which I keep all my tools in, potentially could convert that. (but where would I put all my tools?)

Thanks everyone! Excited to be a part of this community