If in city limits you will have city and county taxes.Make sure that the property you are considering buying does not have a senior exemption making taxes low or that they won an appeal that is fixing to go back up.Look for special assessments and for the city and county what the mill rate has been trending at (going up, staying flat, or decreasing and by how much each month as a percentage).The assessors could have been using low values as well the last few years but with things rising in many markets they will want to reassess to get more money flowing into the county and city coffers.Usually you can look up to sometimes 5 to 10 years worth of bills and assessments online with the county and city tax assessor websites if they are urban and suburban.If it is rural they might not have that info online.

@Renee Zhang You should not decrease it.  

If something seems close and I think I can increase rent/decrease property cost, then I'll give it more attention with running the numbers.

And again those washers in every unit are contributing.See if you can offer a $25 / mo rent decrease to one of the tenants in exchange for mowing the grass. 

Increasing NOI can be achieved by increasing revenue or decreasing expenses or both.Cheers...

Increasing the revenue and/or decreasing the expenses as a direct impact on the value.A common strategy is to purchase an underperforming multifamily, renovate the interiors in order to raise the rents, and refinance after a few years.

Target renting to similar types of people to decrease conflict (e.g target students, target shiftworkers, etc.) 

Minor difference, but it one alleviates the tenant from having to worry about it, and also there's no question if they cut the grass once, it's not going to decrease the rent that month.

This puts the risk of loss on the partner, which decreases the likelihood of jumping on.

Borrower has missed some payments, the more they have missed and the longer it's been since they last paid decreases the value.