Hi Ross and welcome to Kyiv forum!
If that airfare, by any chance, happens to be by Ukrainian Aerosvit, please, browse through this forum and read the feedback on the company.
What do you mean by "good airport", please? KBP is surely not the best airport I've seen in my life, but it's the main international airport in Kyiv, so certainly the best we have to offer here. It's not too far from the city centre (takes from 30min to 1.5hrs, depending on mode of transportation and traffic) and can be reached by public buses and taxis. More info about the airport is available here: tripadvisor.com/ShowTopic-g294474-i3663-k368… and tripadvisor.com/ShowTopic-g294474-i3663-k402…
As for the hotel prices, have you looked at the rates on TA, or the hotels themselves, or the booking sites? The rates on TA are not always fair, so you should better double-check them.
But for less than USD 50 in Kyiv hotels you should get ready for largely Soviet-styled service and facilities. Hostels or apartments can be another options to consider if you travel on a tight budget.
As for knowing anything else, I encourage you to search or read back through this forum - loads of helpful info and tips had been shared here by real travellers and locals. Please, pay attention to the Top Questions about Kyiv in the upper right corner of this page.