I agree with GeorgiaBoy except that I would run the triplex URD in conduit - 1/0 AL should be enough. True, the URD is made for direct bury but could be a nightmare for maintenance if you plan to have it over the long term. URD direct buried will fail - maybe not for many years or maybe in a few years - depending if you "knick" the insulation at installation, soil type, rocks, etc. Conduit is little more expense and a little more forgiving.
FYI - I have a ranch camp that is 620' from the transformer. The underground cable is direct buried 1/0 alum. My voltage fluctuates between 119/238 and 121/241 under load. It serves a 220 AC window unit, freezer, refrigerator, elect 40 gal hot water heater, and of course inside and outside lights. I did get the power company to change the bandwidth on a set of distribution regulators to where the secondary voltage at the transformer averages 126/252. That is at the high end of their tariff requirements.
Not suggesting someone do what I had to do but just saying 275' is very doable with out building a substation. You can do it with no problem without adding another meter.
