[JavaBrewer]

Homes with baseboards installed are two options. Undercut the baseboard and tile fits under or tile up to baseboard and install 1/4 round or base shoe moulding to cover the gap. I have always done the latter.

Is your tile going on wood subfloor or concrete? If wood then you need to install a concrete backer product bedded in thinset and screwed/nailed. If concrete then some sort of crack isolation membrane.