hi Jacqki, first of all there are no restrictions about whether you live in Turkey full time or not, however, when making your application, you must ensure that you will be here long enough for the authorities to process your application (currently around 4 week) as they will hold your passport for that length of time.
Secondly, if you are a tapu holder (ie, you own your own property) you are allowed to take Residency for up to 5 years. However, as a tenant (you must have a tenancy agreement, signed by your landlord) you can take up to 3 years Residency.
Finally, a word of warning if you are planning to 'do it yourself'..... you may have heard that a local resident was deported this week because, when applying for Residency, the wrong information was submitted to the authorities, which suggested that the person was in employment. Although this was proved to be not the case, the deportation went ahead as the process had already been started.
It has to be said that the person involved had actually prepared their own application, with some help from Turkish friends! For a small fee therefore, it may be prudent to use the services of people who are competent and familiar with the process - not to mention of course that they, rather than you, do all the 'running around' in this blistering heat?