Hi Nowton,
Yes, this is quite possible! In fact, I just did the exact same thing this week for the Vancouver Fringe festival. They had two forms for their performers: "main stage" performers and "bring your own venue" performers. The forms were pretty different, but since they were all performers it made sense to collect all the information from both forms in a single table.
What I did was use the largest form for the "Add Form" process within Form Tools, then after adding it, manually added in the fields for the other form through the Edit Form > Database tab. You could do the same, only for the THREE extra forms.
If I'd had all the fields from all forms ready, I would have simply copied & pasted them into a single page and put THAT through as the test submission: this would result in less configuration time later on.
The only odd thing about doing it this way is the URL on the Edit Form -> Main tab. It'll only ever list one of the forms. Not a disaster! But a little weird.
Oh, and in case you don't already know about it, you can redirect to custom "thankyou" pages for each form by including a hidden field:
Code:
<input type="hidden" name="form_tools_redirect_url" value="url here..." />
That'll let you override the (single!) default redirect URL in Form Tools.
Hope this info helps!
- Ben