If they do, use it as a time to upgrade the unit and then absolutely bring it to market rates or increase above market rates if your upgrades warrant it.  

Pay attention to square footage, age of the property, number of bedrooms, number of bathrooms - keep track of every new listing and follow them until they close, get it all on a spreadsheet... (3) look for a multi family, instead of a single (this is an easier way to build equity and create long term wealth), (4) instead of 20% down, try to get a 5% down program - use the cash to upgrade the HVAC, electrical, roof, plumbing etc., (5) live in the multi for a couple of years and keep saving as much money as possible, and (6) start looking for another similar property and do it all over again...  

So upgrades are almost wasted money.

We have deferred upgrades, and could maybe reduce lawn care, but everything else is fixed, including some utilities included in rent. 

If it is any sort of upgrade, you don't need to do it.

It's a Duplex, and I can tell you right off the bat, it's in great condition, just needs cosmetics such as upgrading of the kitchen, and two rooms need carpet removal and new floors.

Repaint all wallsInstalled recess lightsReplaced carpet with laminate flooringInstalled electric security gate on balcony Upgraded new windowsUpgraded new AC unit

If you’re doing a smaller electrical upgrade, you can get away with battery smoke detectors on each floor and a CO (combination or both CO and smoke) within 15’ of the bedrooms.

Trulia and Zillow created a huge upgrade in applicants for me from just Craig’s list and Facebook!

View reportImmediate cash flow even with all 4 units way under market rents, long term tenants 10+ years, 5 y/o roof, new blacktop 2019, all utilities separated and paid by tenants even town water and sewer, huge value add possible with raised rents and minor cosmetic upgrades, each unit is 1620 sq ft 3 br 2 ba  plus full basement with washer and dryer.