Hpa-an is a small town (pop.~40,000) in Kayin State in Southeastern Myanmar
"Bus" (meaning covered pick-up truck crammed with way too many people) from Kyaikto is about 4 hours, 5,000 Kyat. Air conditioned bus, three or four buses a day, from Hpa-An to Kyaiktiyo (the Yangon bus) is around 4 hours and about 5,000 kyat; unlike with the pickup, that takes you all the way to "base camp", with the bus you still have to take another transportation to "base camp", during the day, this will be a pickup, but if you take the night bus or go during the rainy season, you will likely need a motorbike taxi.
Bus between Hpa-an and Mawlamyine is about 2 hours, 1,000 Kyat.
The popular government ferry ("slow boat") from Mawlalmyine to Hpa-An was discontinued as of about December 2012. A fast boat is sometimes available, arranged through the guesthouses in Mawlamyine(70,000 kyat to charter a private boat from Mawlamyine to Hpa-an or 10,000 kyat per person (8,000 in May 2013) from Hpa-an to Mawlamyine.)
Motorbikes can be rented from Soe Brother's Guesthouse for 10,000 kyat/day. We were still able to use one, despite the ban on foreigner driven motos in Bagan and Inle Lake.
Shweyinhmyaw Paya, the pagoda on the northwest end of town has nice views of the sunset; you can watch from a viewing tower or at the side of the river next to the pagoda. There is a ferry below the pagoda for Mt. Hpar Pu on the other side.
The traditional market, just downhill from Soe Brothers guesthouse and across from the red mosque, is where you can hear the Karen/Kayin language spoken and a good spot for food in the morning. The two indoor buildings have housewares, shampoo, mosquito repellent, etc. on the ground floor and clothing and fabrics on the second floors. There is a fruit market outside and a small gold market (beware artificial gems!) around the perimeter. Good value is the hand woven longi fabric in traditional Karen ikat patterns (2000 to 6000 kyats, depending on size, and whether cotton or synthetic "seelon").
For a break, there is a small ice cream shop five doors downhill from the mosque. There is other ice cream in town, but the flavors here, while few in number, are exceptional.
If you buy longi material, and you can't keep the thing from falling off the way the locals do, you may want to have it made up at a tailor with discreet ties or zippers. A good tailor shop is, from the clock tower, take the street next to the bus ticket office, and go uphill towards the monastery. The road curves around to the right, then turn right and you will see the treadle sewing machines in a shop on your right. You can also take the road up from the triangular roundabout, walk uphill past the New Day bakery shop, then turn left at the first intersection. It's on your left, maybe the second building. If you need to travel quickly, they can expedite it for an additional fee.
Traditional massage, head and shoulders and/or feet. Also pedicure, with nail polish (about 2000 kyats), including original multicolor freehand designs (for around 5000 kyats June 2013). From the clock tower, take the road by the bus ticket office towards the monastery. It is the third house on the left, the sign says beauty salon.
Not much to do in the city itself, but beautiful surroundings outside of the city. You can arrange an all-day tour at the Soe Brothers Guesthouse or at Golden Sky Guesthouse (see below for details) - they'll take you out in the countryside, to visit different caves and a monastery. Really nice day.
You can also take a boat across the river to a mountain, or rent bikes to go around in the countryside.
Lonely Planet recommends taking a boat from Hpa-An to Mawlamyine. The boat it recommends no longer exists, but you can sometimes charter a private boat. Ask at Soe Brothers to see about availability. The boat will only run if it has already been chartered by tourists to come up from Mawlamyine; if so, they'll take you back to Mawlamyine for 10,000 kyat/person. (To charter it from Moulmein to Hpa-An is 70,000 kyat for the whole boat.)
All run about 500 kyat per hour (May 2013)
Soe Brothers Guesthouse has maps and can recommend a good Chinese restaurant (Khit Thit, across from Lucky Restaurant), a place to eat breakfast, and a bakery for sweets and coffee drinks -- it even has Torani syrup!
Lucky, a block from the market, has frosted mugs and ice cold bottles of Tiger, also Myanmar on tap, and a generator for power fails, and stays open later than most, not to mention the great pork fried noodles. This is convenient if you are staying at Soe Brothers; in case of power fail or rainstorm, it is a short walk back in the pitch dark.