IMO, relatives are the worst part about having a baby. Especially the unhelpful ones.
Personally, I'm a witch preggo and new mama. If you're not going to get a hotel, you're not going to come visit until I'm good and ready to have you. That's just the way it is. There are people I would be willing to host with a very new baby, and people that I would not be willing to host right away. This time is YOURS and your husband's, and you have every right to have things done the way you want. If they won't get a hotel and pay for it themselves, they must not want to visit that badly.
You're the mama, that means you're the princess, and what you say GOES. 
Good luck!
