hotels are kinda of crazy here, average of 150 USD and up going.
the problem if there is an event they will even be booked fully.

your employers sometime have the option of doing it all for free, but will not offer till u ask, however they cam help u with the visa for sure.

second way is coming via Qatar airways package i think it will suite you.

third way is you come via qatar airways, and make your own hotel prep.

finally i think you need at least 150QR per day for food and transportations.

some hotels i know;
mellinium
regency
grand regency
Al-Busta
merwib
Georeg 2
i think movenpick have good prices as well

welcome to doha in advance