Is it worth it?
I have no idea. That's entirely up to you and your spouse.
To be less glib about it, it depends on what you like/don't like about your current house, what you like/don't like about the potential new house, what you each like/don't like about your current careers, etc, etc. Presumably you bought your first house for a reason, what are you giving up to do this?
I don't know what you mean by "manufactured home". Is there some significant disadvantage to buying this particular house? Why is this new house a quarter of the price of your current house. What trade off are you making there, and is it a trade off that's worth $210-230K??
FWIW, we downsized significantly and used the profits to eliminate my remaining student debt. It was absolutely worth it for us, but that's because we downsized to our dream home. We're much happier here than we were in our more "desirable" home.
Also, don't assume that just because there's a bubble that prices will drop. That's now often how real estate slow downs work. Often prices just fail to rise for awhile, so don't bank on being able to buy back in affordably. Prices might keep rising for awhile and just stay there. It takes a lot for real estate prices to actually drop. So don't cash out of hot market unless you're prepared to be priced out of similar properties in the future.
Basically, if you love your current home and would like to stay there long term, then I would stay put and as you see the prices rise around you, just thank your lucky stars that you bought when you did. However, if you have no real love for your home and could happily hunker down in the new house, then of course, cash in and laugh all the way to the bank.