We ripped out the ugly flooring in the kitchen and refinished the beautiful hardwoods underneath along with new cabinets, ss appliances and granite.

I don't see where you say how big this is, so lets just guess at about $3000 for interior and exterior paint, $2000 for carpet or floor refinishing, and $2000 for small items - all the broken things we've lived with so long we just don't notice, but that buyers and agents will ruthlessly point out.

My question is should I refinish the hard wood floor or put some nice vinyl flooring? 

New kitchen countertops, refinished floors, new paint throughout, new fixtures, updated exterior.

It is also my practice to refinished the hardwood floors whenever possible.

We rewired and replumbed, added AC, redid the kitchen, expanded and redid the main bathroom, added a half bath and laundry room. refinished the original wood floors.

I've had the same experience as Hamp Lee III time and time again and would say if you have real hardwood (i.e. the kind that can be sanded and refinished over and over again) then it would be cost-inefficient to run LVP over it instead of trying your hardest to underwrite tenants well (or hire a PM to handle all of this with excellence) and handling the damage if/when it comes.

If there is anyway to save the wood and have it look good, my gut is to go with refinishing the wood.

I refinished hardwood floors, added washer/dryer hook ups, I supply washer and dryer for my units, replaced cabinets/counter tops, new toilets, bathroom vanity, and add a dishwasher.I try to do the less specialized work my self to save costs, such as replacing the toilet and appliances, remove any junk, and clean.

We refinished the hardwood floors, painted, refurbished the kitchen cabinets, etc.