Adding a bonus room?

[Ju Hyun K.]

I recently bought a new development single family home for my investment, not for a main residence. Now I need to choose a lot of options. Now I am not sure if it would be good to add a bonus room (about 300 sqft, above garage).

Without this bonus room, the house itself is 2100 sqft, 4 bedrooms and 2 and half bath. The bonus room option costs 10K if I add it as a finished room and 3.5K if I add it as an unfinished room. The bonus room will be on the second floor over the garage and after the bonus room added, the total size of the house will be 2400 sqft. If I don't choose the bonus room option, then there will be no room over the garage.

I will immediately rent this house out once it is built. So my only interest is if this will affect the rental price positively and if this will really help reduce the vacancy and increase the resale value.

I am not sure if it is worthy. Please share you thought about this. 

Thank you.