You will need the following:

1. A male character
2. Confirmed Bachelor Perk
3. Long Haul Perk

Make a home at Novac or a simliar place near the outdoors (IE, not the Lucky 38). Every time you kill a Legion raiding party or the like, or when you just find random armor/weapons, don't sell the damaged items, just dump them in your home (even if the item condition is at 0%). After you've done this for awhile, go to your home and take every single weapon and armor you have that is in less than 90% condition. Then fast travel to every single merchant that is near the fast travel point (Gunrunners, Gibson Scrap Yard, etc.). Buy every single weapon or armor at each merchant that is at less than 90%. You will be massively overburned, of course.

Then here's the trick-fast travel to Mojave Outpost. Talk to Major Knight at the front desk. Use the Confrimed Bachelor dialogue option. After a series of dialogues, he will offer to repair every single item in your inventory to 90% for free (he normally can do repairs to 100% for a large fee). This is a one time offer only (hence the reason you are carrying 1,500 pounds of crud).

Then fast travel back to all the vendors and sell the fixed stuff for huge profits. It might take a few restock cycles before they have enough caps to buy it all off of you.

Note that I haven't actually tested this fully. I have Confirmed Bachelor, but not Long Haul, plus I already have nearly 300,000 caps already so I don't really need to do this. But in theory it should work. I don't know if only some of the dialogue choices after you trigger the Confrimed Bachelor dialogue work to get him to make the 90% offer; I would save and test it once to confirm before trying to gather broken stuff to fix and then reload the save.

This is going to cost a decent amount of caps for a lower level player (If it was a higher level character they probably wouldn't need this).

You should try and make sure that something works before you post.

Also, waiting to take out tons of hit squads may take a while and a lot of ammo. Possibly a lot of stimpaks depending on what difficulty you are on. Is doing all of this really worth the trouble?

Well, here is what you have to do get the free repairs at least. Note that it appears that you have to have enough caps to pay for the repairs in the first place, although he doesn't actually charge you them. This is a mid to high level trick. Compare the condition of my items and number of caps I have in the last two screenshots.
http://cloud.steampowered.com/ugc/542930348521791039/6B50C53826ACF5DDFF9CA4E82FE12B4AA1E0B299/
http://cloud-2.steampowered.com/ugc/542930348521793591/A002595AB20DBE6B0B0911010D4F514E5D9B0587/
http://cloud.steampowered.com/ugc/542930348521796380/3FD53C6B98408FFD5383B749C881B4BBF2F4F536/
http://cloud-2.steampowered.com/ugc/542930348521798769/7D09E0D133309BAA74418E0F795F1887232504B4/
http://cloud.steampowered.com/ugc/542930348521794824/63A637E6469D4ADAF53D9EE72750D659BDCAEA62/
http://cloud.steampowered.com/ugc/542930348521802029/1BA505219D9CBF643FC2E710CFBE7B90FBC38500/
http://cloud.steampowered.com/ugc/542930348521801176/B30E53540626B316380920C75498692C50A1A485/
http://cloud.steampowered.com/ugc/542930348521803120/F0D6639577D6FF15F4B9FF6D17F4E02D3131E3E9/

If you have to have enough money for the repairs in the first place, than I doubt they need a 100,000 caps.

Alternatively, this is a free way to get every single unique item you own repaired to 90%. With two companions, even without the Long Haul perk, this can fix a whole heck of a lot of expensive items.

Or you can just play through the game without taking annoying detours and end up with about 450,000 caps in the end and feel like you legitimately made that money.

Just kill all the Fiends, jackels, vipers, legion/ncr, and or Khan you see and take there stuff as you walk around doing other stuff. Repair it until it at 100% put on barter outfit and sell. repeat.

Or you could do Dead Money.

Ok, so I ran around and did this. Instead of using the Long Haul Perk, I just dumped things in a pile at Mojave Outpost.

So, I started with 290k caps. (This is an overwritten save, but the number is right-I just loaded a save right before I talked to Knight.)

http://cloud.steampowered.com/ugc/542930348521803120/F0D6639577D6FF15F4B9FF6D17F4E02D3131E3E9/

So, I piled it on the roof as so...

http://cloud-2.steampowered.com/ugc/542930348526115779/D320033C86D9EFC88CD9B70DECF38C2D938EFB47/

Total weight-1656 pounds. Spent 25k caps on broken stuff from various vendors, leaving me with 265k.

http://cloud-2.steampowered.com/ugc/542930348526124741/8AEE050678B76F85C126B2B18F1E2097354F4C9D/

Would have cost me 193k to fix everything.

http://cloud-2.steampowered.com/ugc/542930348526127245/168E8138F4A3574A22576698F0F73D3635DDB629/

...but it was free.

http://cloud-2.steampowered.com/ugc/542930348526123772/AD9D87E9468A77FA4CE0D22FE5BB584F51E7AF0D/

Once I sold it all (which took forever, especially since Old Lady Gibson is bugged), I had 372k, and I also bought about 15k worth of stuff in the process of selling things.

http://cloud.steampowered.com/ugc/542930348526120906/E30B622776D81F2D799EA85C3484F4AB1B1036F9/

Total profit: 97,000ish caps.

Like you said, it takes forever to sell all of that. Plus, why do you even need 97,000 caps if you already have 290k caps.

Or, you know, play the game anyway you want, not having to keep your stuff at an unsafe location, or giving your character a perk that does not fit the story/character you want. The confirmed bachelor thing was brought up a long time ago. A much better way is to simply have jury rigging and good barter skill. No need to detour every time you want to fix something.
And there are areas in which you can get enough loot that you don't even need to repair items to make a ton of money,

I don't ever get Confirmed Bachelor. People tell me it's a good perk because of the damage, and it is, but my character (in role-play terms) has a fiance, so having that perk would just be strange on his part.

Not to mention, even if you ignore Confirmed Bachelor dialogue checks, some men will still give dialogue, such as Doctor Richards. It's just strange and I don't like having it.

Personally I don't care about "sixuality" perks, because:

• They increase DAM against the targeted six but reduce the number of that six being enemies
  
• There are ways/perks to get much more DAM against everyone, especially with criticals
  
• But most importantly role-playing wise, I think they all pretty much mean your character is very promiscuous(Lady Killer ^^), not just that he knows how to talk to that gender, and I don't play that kind of character
  
• And specifically for the Confirmed Bachelor, I just like my characters liking the same things as me.... the males ones anyway.

I don't remember Doctor Richards, making a move on my male characters.

In terms of role playing, my character is actually bisixual (IE, he has Lady Killer as well) and as well as fairly promiscuous (although his main squeeze at this point is Sarah in Vault 21). I think very few players use Confirmed Bachelor because they don't want to play gay male characters (becuase they are straight males in real life), and I understand that (I almost didn't take the perk for the same reason). Role playing wise, your character doesn't have to be promiscuous to take these traits-he could just be a tease.

It took less than four real life hours total (as you can see by the timing of the posts). If Lady Gibson with her 40k of caps actually worked right, I would have saved an hour of play time. And I've just decided that one my goals this play through is to have at least a million caps before triggering the ending.