New to real estate investing

[Nicalaus B West]

I bought my current residence in 2010 for 20k with the intention of living in it while I made repairs.  The initial goal was to fix it and sell it within a year or so.  I was 20 and knew nothing of remodeling and had no money or credit to hire contractors to make the repairs. Without going into to much depth on how the a 20 year old kid gets a 26K mortgage for a house selling for 20K, I still owe 23K on it because I've been taking the equity out to pay for repairs over the years.

My wife and I are now done with the repairs and are willing to stay here for at least another 5 years. It's been appraised at 80K and my wife and I are wanting to use the money to purchase a multi-family residence.

I've been on bigger pockets for a while and listen to a lot of the podcasts, so while we're searching for multi-family properties I've been using property analysis spreadsheet supplied by the biggerpockets community.

We're working with a realtor on available multi-family properties in our area and now my wife and I are getting nervous.  We currently only have 1 income, mine, and not a lot in savings other than what we'll get when we refinance our current property.  I have credit cards I would like to pay off, a car payment, and student loans.  

I want to invest our money in something that will build our net worth over time. I think purchasing a multi-family property can do that, but I'm worried about having money in reserves for needed repairs, vacancy, etc.  I've tried to include that in our property analysis, but I could use some advice from more experience investors about what path they would take.

Thank you in advance for your advice!

Note: Over the course of the 10 years I've lived in and remodelled the house, I had to do all the work myself so I've accumulated a wealth of knowledge and tools about how to do wiring, plumbing, roofing, drywall, tile, cabinets, etc.  I don't know if that comes into consideration.