Personally, I consider turnkeys the riskiest of real estate investments. Typically you are paying above market price in an area in which you have few to no other contacts besides the turnkey company. The price is above market because you are paying for the convenience of an investment that is (hopefully) fully renovated with tenants in place. Therefore, in low and no appreciation markets, your chances of selling at a profit are minimal.
The turnkey companies are experts in purchasing distressed assets, renovating them inexpensively and quickly then selling them to owners. They are often not experts in property management so usually the rates of eviction and turnover costs are higher while tenant retention is lower than average for that market. Sometimes the renovations are not done well so further maintenance/capex issues are not unusual. Communication is not always good so you will not know about any problems until you don't receive your monthly deposit on time and you ask.
Now what I wrote is all doom and gloom. Many people invest with turnkey companies and do great. But you are putting a lot of trust in these folks to properly represent and manage every step of the renovation, purchase and management of your properties.
