Could probably increase the rent by $100 after the current leases are up.

Since then, I have fixed it up a bit (put in about 35K to increase rents).

Just some general house-hacking considerations-https://www.biggerpockets.com/renewsblog/considera...If any of those help!

Competition for listings have gone down considerably from my experience since September, although well priced homes will still attract a great deal of attention. 

I’m learning the key is to find the best tenant and to take all precautions into consideration.

There are credit forums with all of the tips needed to increase your score (keeping accounts open, increasing credit limits to decrease debt ratios, disputes, etc).

Not sure how much of an issue that would be for you (it would deter me) Another strategy would be to find a multifamily that would pass VA inspection, that needs work and you can put some money into to increase its value.

If you believe that things are as they always will be, (first you should look at the past and see if that is a reasonable assessment of what the future brings) then taking into account: limitations on what you can invest in, your Solo 401(k) "projected" growth, fees & hidden fees, you can't co-mingle funds, you have to carefully manage the process, future tax increases, tax law changes, a national debt that is north of $22 Trillion dollars, unfunded liabilities and and of course inflation, along with possible "bail ins" then you are well equipped to decide if that is a good choice for your style of investing.However, If you are an "opportunistic investor" . . . . you jump at the opportunity when it arises, then you run into some conflicts.

Any special considerations I should be made aware of with a change of landlord mid lease?

We can increase rent to match the area, but it is already cash flowing.