The below is not legal advice and you should hire a lawyer with past subject to experience. 

Registration is only permitted for legal entities, partnerships and natural persons who are 18 years or older.

But I’d’ also ask if the girlfriend is a legal US citizen?

Any ploy, tricks and legalities.

This doesn't replace the need for a MSA that will capture additional clauses needed on a Contractor-SubContractor relationship, this is just a project specific form you would use in addition to the MSA (prepared by your Attorney):This template is for informational purposes only and does not constitute legal advice.

It is legal and very lucrative in some parts of the US. 

My humble advice to anyone attempting to do creative finance is:Creative finance is for experienced investors who have access to capital if anything goes wrong.Learn the lawsDon't use a contract "off the internet", laws vary by state and are also regulated on a federal levelLearn the financing techniques correctlyDon’t skip parts of the processDon’t ever do a “kitchen table” closingUse the proper deedAn attorney can help you with the legal work, but the rest you are on your ownYour guru will not bail you out“Investing” in someone else’s deal by providing a small 2nd loan so the “investor” can pay for “cash to the seller” and for “closing costs” so he can do the deal is a very bad planKnow what problems can ariseLearn the responses and solutions to problems before they are neededKnow everything there is to know about Title and what that meansKnow who a "protected class" individual isLearn the "back doors"Learn human natureUnderstand timelinesUnderstand regulation enforcement (some of these "mistakes" have a 10 year statue of limitations ( they can charge you 10 years AFTER you do the transaction) and carry hefty fines and possible imprisonmentThe court doesn't accept "I didn't know" for an answer"Know that the source of the lead plays a serious role in some states and federallyKnow how much of a "profit" pushes the boundaries to invite an investigationYou can be sued by the seller if you don’t do things correctlyYou are automatically at fault if an investigator or attorney or regulator gets involved.

Pressure to use affiliated servicesHidden fee structuresPROFESSIONAL BOUNDARIES ⚖️Good QIs maintain:Clear fee disclosuresWritten policiesProfessional distanceEthical guidelinesWATCH OUT FOR 👀QIs who:Push investment productsOffer tax or legal advice without credentialsSuggest "creative" solutionsPromise guaranteed returns on exchange fundsBEST PRACTICES FOR VETTING 📋Check multiple referencesVerify professional membershipsResearch online presenceReview complaint historyExamine years in businessINDEPENDENCE MATTERS!

Stop hanging out with your deadbeat buddies who spend all day drinking, talking sports, and otherwise wasting away.

The increased risk is generated by the fact that the owners are relying on the validity of the tenancy in common Agreement for their usage rights, and it is possible to imagine legal circumstances under which this validity might be undermined.- If the subdivider or someone with relationship to subdivider sells, a public report must be done.