So, the difference in price & closing costs would establish firmly the amount.

He hired a mold remediation company and looks like there is significant amount of mold and the cost estimate to remediate is coming to 12k. 

If you have to change a water heater, which now costs around $2000 in Colorado Springs, that is a large unexpected expense that the owner has to pay for.

You can make closing contingent upon finding a tenant that you approve.The fact that they are being transparent about this is actually a really good thing.

But, you can't determine quality by simply what they charge.....as there are plenty of terrible agents who also charge a lot.You'll need to determine what value they bring to you personally and do a cost benefit analysis of whether the cost is worth it to you or not.

How much does it cost for eviction and collection? 

The rules regarding the 45 days for identification of future property and closing within 180 days still apply so as long as you close all the properties within that time you should be fine and pay no taxes for the 1031 exchange. 

We have had a Strctural Engineer out to the property and while we don't need to conduct repairs within the next 5 years or so, we will need to address both of these things at some point and it will likely cost us about 100k.Any advice on selling or holding for the long term?

I could've lent the money out or invested in notes, but I'm more interested right now in asset accumulation.I ended up simply rolling my SDIRA into my current 401k and taking a loan against that, thereby being able to utilize almost 100% of those funds (not quite at $100k in the 401k, but close) and purchase a duplex with a conventional 30 year loan.If I had $150k or more in my SDIRA I would have looked at other options, but with only $50k I found the path I chose to make the most sense.

My carrier, Mercury, opted not to renew because my buildings turned 60 in 2022 (policy cost = $11K).