no traffic? At 450k, you can get a Lynx RS CE or a regular RS (they're basically the same, anyway). Very comfortable cars (despite the stiff suspension), 6CD changer equipped stereo, moonroof, good looks. Should give you around 8-9 km/l in traffic, and 10-12 km/l going to Batangas (if you've got a light foot), and you'll have much more fun driving to Batangas than in any other car.

You can also get a Lynx Ghia for much less, but gas consumption will be comparable or less, and it'll have less poke. The leather seats are a nice touch.

Of course, as default, you could look at a secondhand CVT City or Jazz. Those are nice cars to drive and very, very economical. But make sure the seats are okay with you. Some people (including me) feel that there's not enough thigh support for city driving (sakit sa tuhod). For most people, it's not a problem. And the Jazz is a very cute and very useful car.

Within your budget, you can probably get an 01-03 Toyota Altis 1.6. Boring to look at, but very relaxing cars to drive. And even if you get it in AT, it won't guzzle gas as much as other 1.6 ATs. Same can be said of Civics of the same time period.