Hi Sean,

In general, automatic gearboxes are quite dependable so really it's just down to your preferences. There's a lot of choice on the market in the Polo class of car for that budget. A quick search through the Carzone database threw up loads of options. Here are some, but there are others as well so do your own search and see what you can find. 

1 - 2015 Toyota Aqua - a Japanese market model imported, using a hybrid system like that of the Yaris Hybrid, though doesn't feel as high-quality

2 - 2019 Nissan Micra/March - a bit 'tinny' feeling, but likely very reliable and fuel efficient (cars badged March have been imported second-hand from Japan)

3 - 2017 Nissan Note - larger than the Micra

4 - 2014-2015 Citroen C3 - spacious and comfortable

5 - 2013-2015 Honda Jazz/Fiat - fantastic car - spacious, endlessly reliable (cars badged Fit have been imported second-hand from Japan)

6 - 2013 Mazda 2/Demio - not huge inside, but good to drive and should be reliable (cars badged Demio have been imported second-hand from Japan)

7 - 2013 Peugeot 208 - likeable car, but not many around

8 - 2014 Renault Clio - lots of space, good to drive, a decent option

9 - 2013-2016 Skoda Fabia - great small car, though not everyone loves the 'DSG' automatic gearbox. Not many around with the automatic.

10 - 2015 Toyota Yaris/Vitz - good reputation for reliability (cars badged Vitz have been imported second-hand from Japan)

There's also the SEAT Mii, Skoda Citigo and Volkswagen up! triplets to consider, which are great starter cars, though they are smaller than the Polo, etc.

It's best to focus on cars with as small an engine size as possible to help keep your insurance premium down.