You did it! We figured this one out! It is a truth universally acknowledged (by me for certain) that the Bitchery pretty much knows everything, and really, it's true. Scroll down to see the solution for this HaBO - and many thanks!

This HaBO request comes from Braelyn, who is searching for a Harlequin contemporary title:
Ten to fifteen years ago, when I was a young romance reader, I picked up a second hand contemporary Harlequin romance at the local hardware store. That place had it all.
Sadly I do not remember much about the romance, but what I do remember is the heroine’s digs. She had a houseboat! As she led her beau through the house, every room was a different bright color until they got to the bedroom, which was pure white. Of course, sexy times ensue.
I hope ya’ll can help me out with this as it’s been driving me crazy for years.
I’ve always wanted a houseboat. Though not sure about an all white room because keeping that clean seems like a nightmare. Does this description sound familiar to anyone?

I don’t know if this is the right one, but I remember the heroine in M.J. Rodgers’ Heart vs Humbug (Harlequin Intrigue 350, December 1995)lived on a house boat, and the different colored rooms sounds very familiar. (I remember much more clearly that her bed was a swing of some kind, like the mattress was suspended from the ceiling, if that helps.)
I think in Sarah Morgan’s The Greek Billionaire’s Love-Child the heroine lives for a time in houseboat but if I remember correctly it’s not in a good condition and this one is Harlequin Medical Romance.
You got it straight off AnAu! I googled “Heart vs Humbug” and recognized that cover immediately. Thanks for your help!
I pretty much live for HABO posts. I’m a sucker for the Harlequin queries and the crazy-sauce historicals. If that’s wrong I don’t want to be right 🙂
Glad someone knew this one! Also, in case you want to fall down a reading rabbit hole, Rodgers had a whole series of “Justice, Inc.” Harlequin Intrigues that came out in the mid-1990s. All the titles follow the Something Vs. Something model. You can see a complete list of the series here: http://www.fictiondb.com/author/mj-rodgers~series~justice-inc~4911.htm