Largely, the appreciation in housing prices is coming from both new migrants and investors coming from the East (GTA) as well as international countries (predominately from the middle east).We are also seeing drastic increases in the rental rates which in turn are pushing investment property prices up as well.

Population and economic growth, strong tourism, proximity to other New England cities.

They could also fix it on their own (as some of Scott's buyers do) , increase the value and sell it at higher price than bought, pocketing the difference. 

More eyeballs mean greater viewership, improved SEO, and increased revenue.

It's kind of disconcerting when I can only raise rents by 5% but insurance is increasing by 10% to 15% per year. 

Expand your network, educate potential investors, and leverage social media to increase your reach and influence.

They further out the ripples go from the stone, the less appreciation your receive while the cash flow increases.

The tenant base, on average, tends to be rougher on the properties, moves more frequently, and cannot absorb any rent increases.  

Insurance is now a big factor in the expenses of investment properties, even here in Reno, NV there are areas that have had large increases for single and multifamily properties.

For investors, this can mean boosting rental income or increasing the property value significantly.