My first rental property is a single family 2br/1bath, rents for 1300/month no issues. The exterior is a little dated and there is a huge unfinished (dry) basement. Current appraisal is 155k and I have debt of 128k.
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They were broken into and no longer feel safe in the home.

View report*This link comes directly from our calculators, based on information input by the member who posted.Thank you in advance for your thoughts on this potential purchase.  6 of 8 units have been upgraded and new roofs on each 4 plex in 2017.

So, you may need to consider some additional upgrades there.You have to consider the layout and number of inside units.

Same for replacement of broken or missing parts like broken banisters, broken microwave handle, broken window screens, dog faces left in yard,trash, clean out of cabinets and kitchen, etc.

If you upgrade the exterior dramatically, the building may end up standing out and looking odd / not fitting in...

You have to trust the contractor will have your best interests in mind and not gouge you on the pricing  or respond to tenant related or nonsensical issues (ie, I have a broken slat on my miniblind and need it to be replaced). 

I'm an out of state landlord doing some upgrades in a SFR rental.

What are some little "inexpensive" add-on / upgrades can I do to the home help increase the rent while at the same time giving them the security that I am trying to make this place better for them?

You draw up the document that requires the tenant to reimburse you for the upgrade.