My first potential rental property. Seller has accepted offer but now I'm not sure whether to move forward. DC Metro Area, NoVA

[Victor Yoo]

My in laws have tasked me and my wife to find them a suitable rental property. They have given us around 100k and I've been trying to wrap my head around utilizing this money in the best way possible. We live in Northern VA, and housing costs exceed rental rates. I'm brand new to the world of REI but have been reading and researching on this forum for the past few days as well as Reddit to better understand what constitutes a good investment.

The property I am considering purchasing right now is a short sale Townhouse. I may be missing some vital numbers but will provide what I have at the moment:

2400 Sqft, Townhome, 3Br, 3.5 Ba, 1 Car garage, Deck

Purchase price: 360k Comp Sales : 390k

Down Payment : 90k (98k Closing costs)

Rent-o-meter for this neighborhood : ~$2100

10-15 min commute to Reston, VA, (an up and coming tech hub in this region), Realtor says its a "great area".

Monthly Payments would be $1700 after taxes/insurance/hoa

I thought $400 was a decent positive cash flow, but I failed to factor in vacancy, and other costs. I'm not quite sure what my return on cash is either. From what I gather, savvy investors would rather use the power of leverage and purchase several cheaper properties to achieve more cash flow. I'm nowhere near the 1% rule, and the other 50% rule I fail to remember at this moment. My in laws are not overly ambitious and just wanted to put their savings to some use rather than sit in a savings account. They prefer it be nearby and this property is only 15 mins away from my primary residence. Still, if I were able to provide a much better return on their money, everything else goes out the window.

One of my main concerns is the impact it has on my ability to purchase subsequent rental properties in the future. MY DTI is already high, and my loan officer said it will hit 42% with this new purchase. I'm not sure if that's factoring in future rental income or not. My wife and I make 160k gross a year. However, we currently pay 3300 a month for our primary residence. I understand we would have to wait 2 years regardless to establish rental income before buying a 3rd property. I am very lucky to be in this position and after reading some of your success stories that I too have a chance at passive income and financial independence within the next 10-15 years. However, I'm wondering if this potential purchase will take me out of the REI game before I even get started.

I apologize if this post is unfocused and disorganized but I typed it on a whim. I need to decide on this current townhouse soon. I will try to format this post better later today or tomorrow but greatly appreciate any advice in the mean time, Thank you!!