It has the old roll out windows but none are broken or malfunctioning.

For this reason, if a tenant calls due to a malfunction of the smoke detectors and a technician is dispatched, you can have the following outcomes:Technician determines the smoke detectors were faulty, and replaces - owner chargeTechnician determined the smoke detectors batteries needed replacing - tenant chargeIf written into the lease that the tenant is responsible for such replacement and the detector was easily reachable, - if not or if the tenant is elderly or disabled, assume reasonable accommodation: owner charge=time/labor & tenant charge=battery costWhere the property manager must be mindful is in the allocation of the owner's resources (money).

Tenant agrees to allow Landlord timely access to premises to do maintenance and repair.Tenant will notify Landlord in a timely manner of any damages or problems as they arise, including damages caused by Tenant, malfunction of appliances or fixtures, and water/moisture leaks and spots.Tenant will take care of the premises, keeping them clean and clear of debris.

To me, unless the tenant damaged it causing it to malfunction, you should simply pay it.

The only negative was that one of them had an issue with the motion detector malfunctioning after a few months.

We are not liable for interruption or malfunction in service.

The units arent temperature controlled so no worries for malfunctions there.

We were amazed that a young couple we know just signed a similar rental agreement that stipulates that they are responsible for repairing/replacing any malfunctioning appliance. 

I'd like to have several inspections done (well testing, water conditioning system, hvac and garage door malfunction).

I can go for a short drive and find entire neighborhoods that fit the 2% rule in my area, but I would never invest in this area unless I got an excellent price that allowed for a full redo of the plumbing/electrical/HVAC because the properties are old and undoubtedly have deferred maintenance; landlords/slumlords in the area have been known to do the work themselves; and I don't want to deal with countless minor maintenance issues (eg. leaking faucets, malfunctioning outlets, etc.) that are bound to arise in a property with old and/or shoddy plumbing/electrical/HVAC.I don't mean to sound harsh in any of my response.