Welcome to My Fico Forums, @umarkim101. 
You've gotten some good advice so far.
- First, should I increase 1 card at a time? or multiple at a time?
Increasing multiple cards at at time is a fine if they are soft pull requests. However, if you will entail hard pulls, you may want to spread them out a little to lessen the long-term impact to your credit score. Lenders will tell you before they do a hard pull. Chase will normally hard pull (unless they offer a complimentary automatic CLI.) However, your other three lenders (Capital One, AMEX, and Bank of America) will all process CLI requests with a soft pull. Since you have three Chase cards, I'm not sure if you could ask for a CLI on more than one card with a single HP, but that might be an option.
Since you mentioned spending $10K monthly and putting much of your spend on Chase cards, I'm surprised they haven't offered to increase those $5K or less limits. I would suggest that for any Chase card that you're not spending at least moderately (relative to the existing CL), it may be a wasted hard pull to ask for a CLI. They like to see usage of existing CL. Call Customer Service to request an increase.
Likewise, Capital One likes to see moderate or heavy usage of existing credit limits to approve an increase. You can normally request one every six months by soft pull through their website or app. It's a fully-automated process and you'll get an instant answer and immediate access to the additional limit.
Like Capital One, AMEX and Bank of America allow you to request soft-pull CLIs through their website or app. And again, you'll get immediate access to any increased limits. At higher credit limits, AMEX is known to sometimes go to manual review or to request financial documents. AMEX and Bank of America haven't appeared to me to be as sensitive to usage patterns as Chase and Capital One. However, if you're not using their cards regularly, you may be denied for low usage. A technique here is to (temporarily) shift some of your monthly spend to these cards for several months (3-6) and then retry. I've done this even if it required the temporary loss of some card rewards. IMO, it's a trade-off if you want to increase the limit.
- Secondly, over time, would trying to increase each cc be the ideal scenario? I only really use my chase cards and capital one for reference.
As discussed by @Anonymalous and mentioned in your question (4), raising limits on each card will positively impact both individual and aggregate utilization ratios, which is a good thing! We have some members who don't like to raise their limits beyond a predetermined limit, but much of the rest of our membership likes to raise our limits as much as lenders will allow. In the end, it's a personal decision about how far you want to take it.
- Third, If they ask how much I want to increase my limit, should I have a certain amount?
As @Anonymalous said, ask for the moon. From my experience, lenders will counter with a limit they are willing to approve if you exceed their thresholds. On the other hand, I also believe in being reasonable. If your Chase Freedom card is at $800 and your highest limit is $7,500, it would be unrealistic to ask for a $50,000 limit. However, since you have two other Chase cards with $5K limits, they obviously feel comfortable with that so why not ask for at least $5K on the Freedom? For cards that are already in the middle of the pack relative to your other cards, asking for around 2X or 3X current limit is probably okay. (So for your Chase cards at $5K and highest CL of $7.5K, if you asked for $10K to $15K with Chase, that might be a good goal. Of course, whether they approve is based on overall credit profile, reported income, housing expenses, debts, and perhaps usage patterns of existing credit.)
- Lastly, ... (does) having an increased credit limit generally over time helps build credit?
As explained by @Anonymalous, it's complicated but it's possible that raising limits (which lowers utilization ratios) will increase your credit score. But of course the exact impact depends on all the factors that go into your credit score, and utilization is just one part.
As for credit scores, it's true that the Credit Karma scores may only be helpful for tracking very general trends since they are Vantage scores. To get more accurate FICO scores as used by most lenders, there are some free ways to do it without subscribing to updates. Your AMEX card should give you access to Experian - FICO Score 08. And your Bank of America card should give you access to Trans Union - Fico Score 08. You can also access your Experian score for free if you download the Experian mobile App, which will also give you credit alerts to changes to your file.
@umarkim101 wrote:Hello, I am relatively new to the whole building credit card/credit limit and have been doing research with some mixed reaction, so I thought I would ask here for further clarification.
History: Most of my credit cards are at least 5 years old, and haven't had a credit card increase since. My chase cards are probably close to 10 years old.
My credit cards are as followed:
Chase Freedom - 800 limit
Chase Sapphire - 5k limit
Chase Hyatt - 5k limit
Capital one Quicksilver - 3k
Capital one venture - 7.5k
BoA cash rewards - 3.5k
American express - 1.3k
Those are my total credit cards. If I were to increase my credit limit, which card would you guys recommend that I increase?
First, should I increase 1 card at a time? or multiple at a time?
There's no need to space it out.
Secondly, over time, would trying to increase each cc be the ideal scenario? I only really use my chase cards and capital one for reference.
Sure increasing CL's is a good idea.
With Capital One, BOA, and American Express it's a soft pull.
Any other opinions are greatly appreciated! Thank you so much!
Third, If they ask how much I want to increase my limit, should I have a certain amount?
With Amex say you want a limit of Say 10k or 20k?
With Amex say you want the new limit to be $3900.
With BOA and Capital One ask for a $2500 increase or so.
In the last 6 months, I have used about 10k monthly on average, and have paid everything off on time. But due to credit limits, had to use multiple cc.
Paying everything off on time is not meaningful in terms of the utilization segment of your score.
E.g. if your total limits are 28k, and you've used 7k, and you've paid off all your balances the day after the statement cut, your utilization is 25% But if you paid all your balances the day before the statement cut, your utilization would be zero. In both cases you paid everything off on time.
Lastly, out of curiosity, having an increased credit limit generally over time helps build credit correct?
No, it has no effect on credit scores, unless it lowers your aggregate revolving percentage utilization.
I ask this because my credit score has no moved over the last few years, and I have paid off my cc on time fully, along with paying off my car officially this year.
As mentioned above, paying on time doesn't necessarily mean anything in the utilization segment of your score.
And paying off a loan may or may not be helpful in terms of scoring, depending on whether you have other loans or not.
p.s. I havent had a hard pull to see my credit score,
There's no such thing as a "hard pull" coming from you. If you request your own information, it's not a hard pull.
If you haven't seen your scores, I don't know why you're saying your scores have stayed the same.
Your Amex website will give you your EX FICO 8 score, which is a pretty good measure of how you're doing.
but on creditkarma and myfico it is currently around 740-750. I know those are generally not that accurate, but thought I would add it there.
MyFICO is super accurate. Credit Karma is meaningless.
Thank you so much in advance!
