First Time Investment : Duplex->Triplex/4plex conversion

[Cody Rigby]

Hello!

I am a first time real estate investor looking the following property : 

https://www.redfin.com/OR/Forest-Grove/2418-Cedar-Cir-97116/...

its a pretty large duplex in Forest Grove OR,  the trick is though, its on a lot zoned for a 4 plex so I am looking

into house hacking, converting into a triplex, then living in one unit while renting out the remaining two units

The left garage has been converted to living space, with a living room, half bath, a laundry room with a sink and some counters/cupboards and a bedroom, it is a part of what was an existing 3bd unit

If I were to acquire the asset, I would first attempt to convert that space into its own unit 

The line items as I see (be in mind, I am totally new to this) would be to 

>put up dry wall where the door to the rest of the house is,

>add a shower to the half bathroom 

>install a water heater in the adjacent 3bd unit

> install a kitchen in the laundry room, (
stove , oven , sink, counter space)

>add a shower to the half bath 

Assuming I can convert it to a 3plex, I could at-least cash flow on my investment after I leave 

My plan would be to put minimum down payment of 3.5% (FHA loan) that way I can have a decent amount of capital free to do the renovations

The only concern is when I crunch the numbers to get my ROI, I have no idea

how much its going to cost to convert the additional living space to a third unit

Any experienced investors here know how I can estimate this before I try to make an offer?

at first glance does this project look like its worth taking on or should I shoot for something more turn-key as a first time investor?

Thanks,

-Cody